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The focus of the present study is the learning processes of concepts related to hydrogen bonds, which were developed using a didactic sequence (DS). Based on the perspective of Imre Lakatos, it was observed whether the explanatory models created by upper-secondary students form progressive transition sequences, which are similar to what Lakatos, in his text The History of Science, calls a "problem" that increases the explanatory/heuristic power of the model. To evaluate the evolution of these models, which generally consist of progressive transitions, four phases were developed: (1) the categorization of answers obtained in the DS in Realist, Empiricist or Rationalist zones, as well as an attribution of scores; (2) the determination of a score range for said zones; (3) hierarchical cluster analysis (HCA) and (4) an analysis of the progressive transition of the explanatory models. A continuous review of the ideas expressed by the students during their learning of the subject revealed that a significant share of students progressed conceptually. In a general way, it can be said that the activities developed in the DS contributed substantially to the progressive transition of the explanatory models made by most students. Furthermore, the approach of the DS toward the subject of hydrogen bonds allowed the students to interpret the phenomena studied using their knowledge of Chemistry.

Being able to move between different representations levels (macroscopic, submicroscopic, and symbolic) is important to understand a chemical phenomenon meaningfully. The current study investigated how pre-service science teachers moved from symbolic representation to sub-microscopic representation. A total of 205 pre-service science teachers, first, balanced the three chemical reactions and then drew the reactions' sub-microscopic views if they were able to observe them. The findings revealed that pre-service science teachers are most successful at the symbolic level. Yet, this is not a valid conclusion for the sub-microscopic representation level. The drawings were analyzed concerning atomic size and molecular geometry and found that pre-service science teachers have common alternative concepts. Furthermore, they mostly have a superficial knowledge of the molecular geometry of chemical compounds. In conclusion, because preservice science teachers will teach in their future careers, it is important to encourage them to comprehend chemical phenomena at each representation level and shift between them to prevent alternative concepts they may have.

Students perceive molecular bonding as an abstract concept; therefore, learning this concept seems uninteresting and difficult. A strategically designed learning object (LO), such as in the form of a simulation, can be used to help students acquire accurate mental images and build appropriate schema in addition to providing a concrete learning experience and encouraging knowledge construction. This paper presents an evaluation of the design and development of the "Making Molecules" simulation through students' perceptions of the previous version and recommendations for improving a future version. Data were collected from two online chemistry courses (N = 159) through an anonymous online survey. Results suggest that students responded positively to the use of the simulation. They reported gaining a better understanding of molecular bonding through an interactive learning experience. One of their recommendations was to include more learning tasks related to complex molecules, expressing an interest in learning more about chemistry. This paper provides insights for educators and instructional designers regarding selection and/or design of an LO for optimizing student learning of complex topics.

The rapid onset of the COVID-19 pandemic, also known as the SARS-CoV-2 outbreak, has brought to light how important technology may be to the socio-economic development of a nation, particularly in Africa. The study conducted a narrative review of pertinent literature to objectively assess the effects of two types of emerging digital technologies (Artificial Intelligence [AI]) and nanotechnologies in Africa. The results showed that emerging technology-related research, development, and deployment are happening throughout Africa. Nanotechnology and AI have had a substantial impact in many spheres of African economies. The study, however, acknowledges in its conclusion that not all African nations have derived the same benefits from emerging technologies, including the digitalisation processes. There are still large disparities in the accessibility of technology and digital skills in several rural and underdeveloped areas in Africa. Thus, recommendations on how to close these gaps are provided for all African countries to profit more consistently from the emerging technologies and the digitalisation processes.

The biology education literature includes compelling assertions that unfamiliar problems are especially useful for revealing students' true understanding of biology. However, there is only limited evidence that such novel problems have different cognitive requirements than more familiar problems. Here, we sought additional evidence by using chatbots based on large language models as models of biology students. For human physiology and cell biology, we developed sets of realistic and hypothetical problems matched to the same lesson learning objectives (LLOs). Problems were considered hypothetical if (i) known biological entities (molecules and organs) were given atypical or counterfactual properties (redefinition) or (ii) fictitious biological entities were introduced (invention). Several chatbots scored significantly worse on hypothetical problems than on realistic problems, with scores declining by an average of 13%. Among hypothetical questions, redefinition questions appeared especially difficult, with many chatbots scoring as if guessing randomly. These results suggest that, for a given LLO, hypothetical problems may have different cognitive demands than realistic problems and may more accurately reveal students' ability to apply biology core concepts to diverse contexts. The Test Question Templates (TQT) framework, which explicitly connects LLOs with examples of assessment questions, can help educators generate problems that are challenging (due to their novelty), yet fair (due to their alignment with pre-specified LLOs). Finally, ChatGPT's rapid improvement toward expert-level answers suggests that future educators cannot reasonably expect to ignore or outwit chatbots but must do what we can to make assessments fair and equitable.

The laboratory practice "Primary culture and directional differentiation of rat bone marrow mesenchymal stem cells (BMSCs)" is part of a required course for sophomore medical students at Tongji university, which has been conducted since 2012. Blended learning has been widely applied in medical courses. Based on a student-centered teaching philosophy, we reconstructed a comprehensive stem cell laboratory module with blended learning in 2021, aiming to facilitate students in enhancing their understanding of the multi-lineage differentiation potential of stem cells and improve their experimental skills, self-directed learning ability, and innovative thinking. First, we constructed in-depth online study resources, including videos demonstrating laboratory procedures, a PowerPoint slide deck, and published literature on student self-learning before class. In class, students performed a primary culture of BMSCs, freely chose among adipogenic, osteogenic, or chondrogenic differentiation, and used cytochemical or immunofluorescence staining for identification. After class, the extracurricular part involved performing quantitative polymerase chain reaction to examine the expression of multi-lineage differentiation marker genes, which was designed as an elective. After 2 years of practice, positive feedback was obtained from both students and faculty members who achieved, the learning goal as expected. The reconstructed stem cell laboratory module provides comprehensive practice opportunities for students. Students have a better understanding of BMSC at the molecular, cellular, and functional levels and have improved their experimental skills, which forms a basis for scientific research for medical students. Introducing blended learning into other medical laboratory practices thus seems valuable.

Teaching chemistry and biology students about biologics design remains challenging despite its increasing importance in pharmaceutical development. Monoclonal antibodies, commonly called mAbs, are the most popular biologics. They have been developed into drugs to treat various diseases in the past decades. Multiple challenges exist for designing proper formulations to stabilize mAbs, such as preventing aggregation and mitigating viscosity. Molecular modeling and simulations can improve pharmaceutical products by examining the interactions between mAbs and other compounds, such as excipients. To introduce students to biopharmaceuticals, eight students at the Stevens Institute of Technology participated in a semester-long course to learn the challenges of pharmaceutical development and different computational skills to study biologics design. The students started with a limited background in this field. Throughout one semester, they were introduced to various literature and software tools for modeling antibodies and studying their interactions with excipients. This paper aims to develop a course structure to be replicated at other universities and institutions to teach biopharmaceutical development to students.

Anaerobic digestion is a complex biochemical process that is represented by the stoichiometric Buswell's equation. Buswell's equation is the study of the interface among biochemistry, mathematics, and chemistry. Students often have difficulty in understanding the nature of biochemical stoichiometry. Buswell's equation is significant for the calculation of the quantity of biomethane. Although the general formula CxHyOz of organic pure substance or mixture has been well studied, the Buswell's equation for biomolecules containing phosphorous has rarely been explored. The aim of this article is to study the nature of Buswell's equation using the H-atom method. The new general Buswell's equation, which contains phosphorous, is deduced from the H-atom and algebraic methods.

Representations in chemistry are the tools by which students, instructors, and chemists reason with chemical concepts that are abstract. Although representations are regularly used within the chemistry classroom, there is more to uncover regarding the ways students interact with representations when given chemistry tasks. This study aimed to address this gap in knowledge. In this study, eighteen students enrolled in second semester general chemistry were recruited for data collection. Semi-structured interviews were utilized to observe how students approached a similar set of dipole-dipole interaction tasks when given four distinct representations. Analysis of the data revealed that students' approaches to these tasks were affected by the newly explicit features present within each representation. Additionally, the ordering in which the representations were presented to the students influenced the specific features students took notice of and implemented into their approaches to the tasks. These findings can better inform instruction and future research involving chemical representations such that students will form a solid foundation in working with and pulling relevant information from various representations when solving chemistry tasks.

Most biology undergraduates learn about mutations in multiple classrooms throughout their college career. Understanding personalised genome test results, genome editing controversies, and the appearance of new variants of viruses or antibiotic resistant bacteria all require foundational knowledge about mutations. However, the abstract nature of molecular processes surrounding mutations makes them one of the more difficult topics for students to understand and apply. Instructors need valid assessment tools to document student understanding and tailor their instructional methods to address student knowledge gaps. We describe here the development and validation of the Mutations Criterion Referenced Assessment (MuCRA). This formative assessment was developed through an iterative process involving expert feedback and student responses to both open-ended and multiple-choice questions. The final MuCRA is composed of 10 multiple-choice questions aligned with three learning objectives. The item difficulty for each question was between 0.32-0.65, while the discrimination index ranged from 0.31-0.75 and the reliability (KR20) for the MuCRA was 0.69. The congruence analyses demonstrated distractors are capturing student misconceptions in 9/10 questions. These data indicate that the MuCRA can be used to reliably assess student learning and common misconceptions about mutations.

Appealing to students' affect in academic settings, such as demonstrating chemistry's relevance to their life, is one strategy instructors may use to support students' in learning. This study investigates the types of connections that students make to organic chemistry when responding to an open-ended writing assignment. Students enrolled in an introductory level organic chemistry course were asked to choose and write about an organic molecule they felt was important to their life, in doing so students wrote about the molecule's relevance to their life. Analysis of the writing was supported by semi-structured interviews with a subset of the students in which they discussed their approach to completing the assigment. Conclusions from this study suggest that students successfully made connections between their chosen molecule and their life. Considered through the lens of relevance, students can both seek and find relevance in organic chemistry topics on a personal, societal, or vocational level; and therefore may reinforce their comprehension and appreciation of chemistry.

Central to conceptual understanding of STEM disciplines is visuospatial processing. Despite its acknowledged role in assuring learners' success, less is known about the underlying reasoning students must employ when solving 3-D problems and the ways in which gaining an understanding of this can inform formative assessment and learning in STEM education. Chemists must utilise their spatial understanding when visualising 3-D structures and processes from 2-D representations and so this exploratory practitioner-researcher study sought to identify the ways in which secondary school chemistry students reason when explaining their predictions about molecular geometry, and how the use of certain modalities was linked to assessed accuracy. Coding of students' verbal and written responses to the research task revealed that students employed multiple reasoning strategies and conceptual resources to facilitate use of analytical heuristics and imagistic reasoning. Analysis of students' verbal responses and spontaneous gestures provided insight into the extent of imagistic vs. analytical reasoning and the finergrained conditions which promoted their use. Importantly, it was observed that despite being instructed on the use of VSEPR theory to find analytical solutions, some students exhibited preference for alternative reasoning strategies drawing upon imagistic reasoning; showing more nuanced and varying degrees of accuracy through their verbal responses and representations gestured in 3D space. This work has pedagogical implications as use of specific reasoning strategies and the identification of key conceptual resources is not readily promoted as classroom practice for learning or assessment. This study therefore raises questions and contributes to the evidence base for attending to learners' visuospatial thinking, as revealed through the multiple modalities they may use to assist and communicate their understanding, and highlights the significance of this to formative assessment in Chemistry and STEM Education.

Education in organic chemistry is highly reliant on molecular representations. Students abstract information from representations to make sense of submicroscopic interactions. This study investigates relationships between differing representations: bond-line structures, ball-and-stick, or electrostatic potential maps (EPMs), and predicting partial charges, nucleophiles, and electrophiles. The study makes use of students' answers in hot-spot question format, where they select partially charged atoms on the image of a molecule and explanations. Analysis showed no significant difference among students when predicting a partially positive atom with each representation; however, more students with EPMs were able to correctly predict the partially negative atom. No difference was observed across representations in students predicting electrophilic character; while representations did influence students identifying nucleophilic character. The affordance of EPMs was that they cued more students to cite relative electronegativity indicating that such students were able to recognize the cause for electron rich/poor areas. This recognition is central to rationalizing mechanisms in organic chemistry. This study offers implications on incorporating EPMs during instruction and provides evidence-based support in how EPMs could be useful in promoting learning on topics that relate to an uneven charge distribution.

Asking students to explain why phenomena occur at a molecular level is vital to increasing their understanding of chemistry concepts. One way to elicit students' mechanistic reasoning and guide construction of knowledge is through Writing-to-Learn (WTL), which is a promising approach for students in organic chemistry courses. In the design of WTL assignments, rhetorical aspects provide an authentic context by designating a role, genre, and audience for students. This context can support students' learning, but, if the rhetorical aspects misalign with the learning objectives of the assignment, they can hinder students' ability to achieve these objectives. In this project, we designed a WTL assignment about a base-free Wittig reaction, which we implemented in an organic chemistry laboratory course. Here, we explore how changes in the rhetorical aspects of this assignment can influence the way students explain two different comparisons of reaction mechanisms. We consider how students use explicit and implicit properties and how the use of these features compares within the context of the reaction. Results indicate that, when the rhetorical aspects align with the learning objectives of the assignment, students provide more productive elaborations that use both explicit and implicit properties. This is supported by both the analysis of students' writing and students' feedback about the assignments.

Innovations in medical education, including the integration of narrative-based tales, are transforming the way complex biochemical concepts are taught and understood. In this "Idea to Explore", the essence of integrating tales that personify molecules and depict biochemical processes as engaging stories to enhance student engagement, promote active learning, and improve knowledge retention is discussed. It also explores the effectiveness of scientific discovery games and traditional scientific stories in deepening students' interest in biochemistry. Highlighting the potential of narrative methods to make biochemistry more accessible and engaging, educators are encouraged to adopt creative teaching tools that promote critical thinking, problem-solving, and communication skills, thereby inspiring active participation, and lifelong learning in biochemistry.

Genetics is a subject that is quite difficult according to students. Various strategies and methods are used to understand genetics in learning to have genetic literacy. One way of increasing genetic literacy in students is to apply genetic problems based on an online discussion in genetics lectures. The research was conducted to determine the effect of genetic problem-based online discussion on increasing students' genetic literacy. The research design used a pre-posttest control group design. It was carried out experimentally on three treatment groups: the genetic problem base of students, the genetic problem base of educators--students, and the genetic problem base of educators. According to the genetic literacy domain, genetic literacy is measured through multiple-choice tests, including genetic models, meiotic models, and molecular models. Manova analyzed the value of gene literacy, and a post-doc further test was performed to differentiate genetic literacy in the three treatment groups. The results showed that genetic literacy increased in all treatment groups, with the highest increase in the group that applied a genetic problem base focused on student problems.

The study diagnosed chemistry teacher trainees' difficulties in naming and writing structures of spiro and bicyclic compounds. The case study design was conducted in a constructivist environment to enhance chemistry teacher trainees' ability to construct, represent, and interpret the structural formulae of spiro and bicyclic compounds. Purposive sampling technique was employed to select 126 1st-year chemistry teacher trainees from University of Education, Winneba for the study. The results revealed that chemistry teacher trainees had difficulties in naming and writing structural formulae of spiro and bicyclic compounds. However, through the effective use of molecular model kits in teaching naming and writing structures of spiro and bicyclic compounds, these chemistry teacher trainees became conscious of IUPAC rules for naming and writing spiro and other cyclic compounds. At-test conducted indicated that a statistical significance difference existed between students' performance before the implementation of the intervention and after the intervention. It is recommended that chemistry teachers should adopt the use of molecular model kits in teaching concepts of organic nomenclature.

Analogies and modelling have been developed and applied in learning and teaching science to facilitate students' understanding of abstract concepts, such as atomic structure. Considering few studies focus on comparing the effects of two teaching strategies--analogy-based teaching (ABT) and modelling-based teaching (MBT)--this study aims to compare the effects of ABT and MBT on high school students' content understanding and transferability of atomic concepts in science. Implementing a quasi-experimental design with pre-post-delayed tests, the study compared learning outcomes achieved by the MBT group (N = 68) and the ABT group (N = 69). The results showed both MBT and ABT could improve students' content understanding and promote transferability. However, the MBT group significantly outperformed the ABT group in terms of generating initial models and overall transferability. Although there was no difference in content understanding, or near or far transferability, at post-test between the two groups, the MBT group maintained more extended memory of atomic structure on the delayed post-test. Moreover, qualitative analysis of students' drawings of atomic models revealed that both groups were able to develop and transfer their models, but inadequate scientific knowledge affected the quality of the transfer product. These findings have implications for designing and implementing instructional approaches that leverage analogy and modelling in the science class.

The concept of hybridisation is one of the most difficult concepts for chemistry students to grasp at all levels of learning. Research showed the students conceptual difficulty ranged from their lack of the prerequisite knowledge for grasping the topic hybridisation to chemical bond formation and orientations of atomic orbitals. This study investigated the difficulties Senior High School Students face in learning hybridisation. The study adopted a mixed-method approach using the sequential exploratory design. Purposive sampling was used to select six schools that offer elective chemistry subject. Simple random sampling was then used to select 120 Senior High School form 1 students to take part in the study. Convenient sampling was used to interview 24 students from the sample. Hybridisation Achievement Test (HAT) and Semi-structured interviews were self-constructed and used to collect data. Descriptive statistics and Content analysis were used to analyse the data. Results showed that, majority of students had difficulties in explaining the concept of hybrid orbitals, writing the electron configuration of [subscript 6]C, explaining the effect of hybridisation on formation of chemical bonds in [subscript 6]C, and type of hybridisation and shapes of compounds such as NH[subscript 3], OF[subscript 2], BCl[subscript 3], CO[subscript 2], SiO[subscript 2], C[subscript 2]H[subscript 2], BeF[subscript 2] and C[subscript 2]H[subscript 4]. The study also showed that students had difficulties in explaining and demonstrating the formation of C = C double bond in ethene and other compounds. Equally students were challenged in demonstrating the differences between the formation of sigma and pi bonds in compounds. Students had difficulties in using electron orbital diagrams to explain the shape of CO[subscript 2] as linear. The study concluded that Senior High School form 1 chemistry students in the Upper West Region of Ghana lacked the most basic and fundamental concept of hybridisation. Teachers need to use conceptual change instructional approaches to teach hybridisation in order to foster students' understanding and reduce misconceptions.

Development of cognitive skills is critical for developing the right conceptual ideas in chemistry. Atomic structure, bonding, and associated properties are taught as parts of high school chemistry courses worldwide. The cumulative build-up of misconceptions about the periodic table is to blame for students' poor performance on atoms and bonding-related topics. This is primarily due to a lack of appropriate cognitive abilities. The periodic table is a fundamental organizing principle in chemistry that high school students are introduced to. The purpose of this study is to determine the commonalities among learners' misconceptions about various aspects of the periodic table in two distinct countries. This study had two objectives. To begin with, it demonstrated if learners from different locations developed the same type of alternate concepts. Second, it aided in discovering the most prevalent alternate conceptions in learners' minds regarding the periodic table. This study enrolled 97 students from India and 78 students from South Africa. The quantitative data for this investigation were gathered using a modified BRI. It is noticed that, despite disparities in their social environments, high school students generally possess similar alternate conceptions that act as a learning barrier at their higher level of learning.

Cognition and brain homeostasis depends on cerebral blood flow to secure adequate oxygen and nutrient distribution to the brain tissue. Altered cerebral blood flow has previously been reported in individuals diagnosed with autism spectrum condition in comparison to non-autistics. This phenomenon might suggest cerebral blood flow as a potential biomarker for autism spectrum condition. Major technological advancement enables the non-invasive and quantitative measurement of cerebral blood flow via arterial spin labeling magnetic resonance imaging. However, most neuroimaging studies in autistic individuals exploit the indirect blood oxygen level dependent functional magnetic resonance imaging signal instead. Therefore, this review examines the use of arterial spin labeling to further investigate the neurobiology of the autism spectrum condition. Followed by a comparison of results from molecular imaging and arterial spin labeling studies and a discussion concerning the future direction and potential of arterial spin labeling in this context. We found that arterial spin labeling study results are consistent with those of molecular imaging, especially after considering the effect of age and sex. Arterial spin labeling has numerous application possibilities besides the quantification of cerebral blood flow, including assessment of functional connectivity and arterial transit time. Therefore, we encourage researchers to explore and consider the application of arterial spin labeling for future scientific studies in the quest to better understand the neurobiology of autism spectrum condition.

This study was conducted to determine the differences in the conceptual understanding of 52 Turkish students who were taught with a scientific argumentation approach in grade 12 chemistry. The concept test was administered to the participants as a pre-test and post-test, and it contained two questions. The first had two sub-questions had two steps. The second had six sub-questions. The researcher of the current study, who was well-versed in chemistry education, and a chemistry teacher, expressed their views regarding the content validity of the concept test. The criteria scales and scoring rubrics were prepared by the researcher to evaluate the test in terms of a conceptual understanding of hydrogen bonding. This study, which thoroughly aims at learning the effects of scaffolding with argumentation, applied mixed-methods research to reveal students' understanding of hydrogen forces and to determine schemas by drawing. In quantitative analysis, the mean, median, and standard deviation values of the data collected from the students were considered. In qualitative analysis, the drawings and explanations of the students on the concept tests applied before and after the education were discussed. According to the results of the concept tests, improvement in the conceptual understanding of the students before and after the argumentation-based teaching could be observed; however, half of the students still evidently had a rote understanding. In conclusion, the scientific-argumentation-based teaching approach was effective in developing their conceptual understanding. Recommendations are made as a result of this study.

A deep understanding of organic chemistry requires a learner to understand many concepts and have fluency with multiple skills. This understanding is particularly necessary for constructing and using mechanisms to explain chemical reactions. Electrophilicity and nucleophilicity are two fundamental concepts to learning and understanding reaction mechanisms. Prior research suggests that learners focus heavily on explicit structural features ("e.g.," formal charge) rather than implicit features ("e.g.," an open p-orbital) when identifying and describing the role of electrophiles and nucleophiles in reaction mechanisms; however, these findings come from small-scale, interview-based investigations with a limited number of reaction mechanisms. The work reported herein seeks to further explore the meaning learners ascribe to electrophiles and nucleophiles by evaluating 19 936 written explanations from constructed-response items asking "what" is happening in reaction mechanisms and "why" it happens for 85 unique reaction mechanisms across a yearlong postsecondary organic chemistry course. To analyze these data, we developed an electrophile rubric to capture learners' level of explanation sophistication ("Absent," "Descriptive," "Foundational," and "Complex"); this electrophile rubric is complementary to a nucleophile rubric previously reported in the literature. Our data show proportional levels of explanation sophistication for electrophiles and nucleophiles ([tau][subscript b] = 0.402) across these written explanations of reaction mechanisms. We note that learners' explanations of nucleophiles tend to be at a higher level than their explanations of electrophiles. While this finding does support prior literature reports, we also found that explanations of mechanisms involving reductions of pi-bonds ("e.g.," carbonyls) tended to be more sophisticated for electrophiles than for nucleophiles. Overall, our results support the claim that learners are able to discuss both electrophilicity and nucleophilicity; however, learners discuss electrophilicity and nucleophilicity at different levels of sophistication where nucleophilicity predominates for most reaction types.

In recent years, chemistry educators are increasingly adopting immersive virtual reality (IVR) technology to help learners visualise molecular interactions. However, educational studies on IVR mostly investigated its usability and user perceptions leaving out its impact on improving conceptual understanding. If they evaluated students' knowledge gains, they tended to use information recall tests to assess knowledge gains. Employing interviews and diagram-drawing tasks, this study explored how students' conceptual understanding of the nature of hydrogen bonds and the shape of snowflakes changed through a collaborative IVR experience on snowflakes. Participants were 68 undergraduate chemistry students. Videos of pre-/post-interviews and student-generated diagrams were analysed. The results indicated a marked improvement in students' conceptual understanding of the nature of hydrogen bonds among water molecules in snowflakes. After IVR, 57 students provided scientifically acceptable explanations of the nature of hydrogen bonds. Improvements in students' understanding were related to the intermolecular nature of hydrogen bonds, the role of lone pairs of electrons in forming hydrogen bonds, and molecular interactions in 3D space. This study suggests that collaborative IVR could be a powerful way for students to visualise molecular interactions, examine their alternative conceptions, and build more coherent understanding. Implications for the design and implementation of IVR activities for science learning are discussed.

Recent studies have reported a growing trend of using student-generated diagrams for assessment in science teaching and research. However, many educators tend to use diagrams to explore students' perceptions of scientists and their work rather than explore conceptual understanding of abstract concepts. In this study, we used diagrams to investigate students' conceptual understanding of the nature of hydrogen bonds among water molecules in snowflakes. Participants were 70 first- and second-year university students. Following a sequence of interview prompts, the students drew diagrams to illustrate the interactions amongst water molecules in snowflakes. Sixty students' diagrams were analyzed inductively using a constant comparison method. Most diagrams showed that the students did not have major challenges drawing the water molecule structure, recognizing polarity of a water molecule, or recognizing the intermolecular nature of hydrogen bonds. However, the diagrams revealed varied ways in which students conceptualized the formation of hydrogen bonds. A third of the diagrams revealed students' alternative conceptions about the role of lone pairs of electrons in the formation of hydrogen bonds. Most diagrams which showed a good understanding of the nature of a hydrogen bond revealed students' difficulties in recognizing molecular interactions in a 3D space. Our findings suggest that student-generated diagrams can provide a powerful way to understand students' conceptions of abstract science concepts.

The present investigation aims to analyze the knowledge levels and chemical representation levels of pre-service primary school teachers (PPSTs) on the experiment of distillation. For this purpose, the cross-sectional survey technique, one of the quantitative research designs was employed. The study was carried out at a Faculty of Education in the Aegean Region of Turkey with 79 freshman pre-service teachers enrolled in the Department of Primary Education. This group is of particular interest as they are the last class who had taken the General Chemistry course since this course was removed from the curriculum in 2018. A Distillation Experiment Worksheet (DEW), which consisted of 9 open-ended questions involving the macroscopic, sub-microscopic, and symbolic representations was used as data collection instrument in the study. The worksheets were analyzed with the document analysis method according to the categories created within the scope of the chemical representation levels, and these categories were established in line with direct statements of the PPSTs. Results indicated that PPSTs confused the heterogeneous and homogeneous mixtures, physical properties such as volatility and density, and they were unable to differentiate between boiling and evaporation. The most crucial result of the study was that the PPSTs had difficulties in establishing a relationship between macroscopic and sub-microscopic representations. For this reason, they could not demonstrate the interactions between solvent and solute molecules at the submicroscopic level during molecular dissolution and they could not predict how the intermolecular interaction changes during the condensation and the distance between the particles. Based on the results of this analysis, our study provides several recommendations for lecturers in the last part of this paper.

Collaboration is regarded as one of the core competences of the 21st century when it comes to complex problem solving. In response to high dropout rates among STEM students, we developed a digital-collaborative intervention on a difficult topic, MO theory, for first-year chemistry students. First, students work independently in a Digital Learning Environment (DLE). Afterwards, they collaborate in small groups and create Concept Maps on MO theory. We evaluate this intervention through knowledge tests, tests of attractiveness, cognitive load, and usability during the DLE and concept mapping process, as well as audio and screen recordings during the collaborative group processes. This paper presents the detailed study design together with results from a first study in January 2021, focusing on the practicability of the intervention and students' feedback. Overall, each small group succeeded in creating a Concept Map. Students rated all phases of the intervention as attractive, with high usability and low cognitive load, although the interactive videos scored better for attractiveness and usability than the concept mapping process. On that basis, first adjustments for a second cycle of the intervention, which will be conducted in January 2022, were derived.

Understanding chemical models can be challenging for many university students studying chemistry. This study analysed students' understanding of molecular structures using the Lewis structure as a model, and examined what hinders their understanding. We conducted pre- and post-tests to analyse students' conceptions and changes in them. The measures contained multiple-choice questions and drawing tasks testing their understanding of concepts, such as polarity, geometry, charge or formal charge and expanded octet. The pre-test revealed a lack of knowledge and several misconceptions in students' prior knowledge. For example, the concept of polarity was well-known, but the combination of polarity and geometry appeared to be difficult. For some students, the representation of molecules was intuitive and lacking a systematic approach. Certain students used mnemonics and draw ball-and-stick models connected to surficial representations. After the chemistry courses, the conceptions and drawings had generally changed, and the level of the students' knowledge increased markedly. Although, fewer ball-and-stick models were drawn in the post-test, some students still used them. The main result was that students who drew ball-and-stick models in the pre-test were less capable of drawing the correct Lewis structures with electrons in the post-test. In addition, heuristics seem to hinder learning and some concepts, such as resonance, remained difficult. This is probably due to the fact that understanding molecular structures requires systemic understanding, where several matters must be understood at the same time. Our study highlights that the understanding of molecular structures requires conceptual change related to several sub-concepts.

The purpose of the study is to determine the knowledge and awareness of gifted children receiving education in the Science and Art Center on nanotechnology. The descriptive survey model was used in the study. The purposeful sampling method was chosen and a total of 160 students receiving education in two Science and Art Centers located in the city of Antalya in the 2018-2019 academic year were included in the study. The students consisted of 5th, 6th, 7th, and 8th-grade students. The study tested whether the nanotechnology knowledge levels of gifted students differ according to the variables of students 'gender, grade level, knowledge source, parents' education level, and occupation. According to the findings, while the students' knowledge and awareness of nanotechnology did not create a significant difference in terms of the gender variable, it was determined that as the grade level increased, the knowledge and awareness level also increased. Also, it was determined that as the parents' education level increased, the students' knowledge on nanotechnology increased and that the knowledge and awareness of students whose parents are engineers or doctors were higher compared to the other students.

Students often have difficulty understanding abstract concepts in chemistry and a low spatial ability, especially in visualizing intermolecular interactions at the submicroscopic level. Therefore, this study aims to analyze the spatial ability of students by using a 3D virtual representation as they study the curriculum topic of molecular geometry. The research was conducted with 13 male and 23 female year 10 secondary students in Jakarta, Indonesia. A qualitative methodology was employed to analyze students' spatial abilities while they undertook learning activities using 3D virtual representation. Data collection included a spatial assessment, a quiz about prior knowledge, student worksheets, interviews, observation sheets, reflective journals, and a molecular geometry test. Learning was carried out in three stages; engage, explore, and explain. The results of the research show that students' ability in spatial orientation is low whereas their ability in spatial relationships that involve using mental manipulation and rotation of 2D or 3D objects is more developed. Students employ this approach to develop their understanding of molecular geometry.

This study aims to develop a measurement tool to measure pre-service science fields teachers' (PSSFT') attitudes towards nanotechnology. For this purpose, a five-point Likert-type scale consisting of 55 items was applied to 373 PSSFT who enrolled in science fields (Science, Chemistry, Biology, Physics) at the grades 1st, 2nd, 3rd, and 4th at a public university in Turkey. The exploratory factor analysis (EFA) determined that the scale had a 3-factor structure consisting of 24 items and the factors explained 55.854% of the attitude variable's total variance. Verification of the model was tested by applying confirmatory factor analysis (CFA). The CFA data were obtained from 770 PSSFT enrolled in science fields at the grades 1st, 2nd, 3rd, and 4th at two different public universities in Turkey. The results obtained from CFA were in agreement with the model obtained by EFA. Cronbach's alpha (Cr-[alpha]) reliability of the scale was calculated to be 0.926. Findings from the validity and reliability analyses show that the scale is a valid and reliable measurement tool that can measure PSSFT' attitudes towards nanotechnology.

Research has shown that spatial ability plays a key role in understanding STEM (Science, Technology, Engineering, and Mathematics) content, including chemistry. Conservation of Matter (CoM) is an essential but challenging topic for chemistry students of all ages to grasp; it is often taught in a way where students memorize it but do not learn what it means conceptually. This research explored the relationship between understanding spatial ability and conceptual understanding of CoM in middle school students. CoM was examined in two ways using the Conservation of Matter Assessment (CoMA): through questions on conservation of atoms and the conservation of mass. Spatial ability was measured using the Purdue Spatial Visual Test: Rotations (PSVT). Significant, moderate correlations were found between spatial ability and understanding of CoM prior to and after a chemistry unit including instruction on CoM; the correlation was stronger after instruction. Scores on the PSVT and CoMA significantly increased pre to post instruction. The data show spatial ability may impact students' understanding of CoM, which contributes to the literature on factors that impact students' understanding of chemistry. Additionally, it provides evidence that teachers should consider including spatially rich experiences in their chemistry classroom, such as making explicit connections between the areas of Johnstone's Triad.

Some science subjects are often perceived to be difficult and boring by students due to their nature and the way they are taught. This study sought to check the effectiveness of the technology-enhanced instruction method with comprehensive use of virtual labs and animations in teaching nerve cells' (neurons and glial cells) structures and functions. Mayer's cognitive theory of multimedia learning provided the theoretical model to frame the study. This study used a quasi-experimental design of pre-test and post-test where four secondary schools all from the southern province of Rwanda were selected from two different districts. Two schools from Ruhango District were assigned to the experimental group while the other two schools from Muhanga District were assigned to the control group. The study involved 168 students, 83 forming the control group, and 85 forming the experimental group. The biology test based on nerve cells was used to assess the effect of teaching strategies before and after learning. The collected data were analyzed using SPSS version 23, and we computed a multivariate analysis of variance (MANOVA) and repeated measures ANOVA. The results indicated that the students who learned nerve cells by use of technology-enhanced instruction of virtual labs and animations outperformed those who learned with conventional methods (M. exp. = 80.41% with SD = 10.32 versus M. cont. = 47.11% with SD = 10.68 and a p-value < 0.05). The results also indicated that after learning with virtual labs and animations, the number of students who were able to perform each of the 20 questions of the test increased considerably. The study recommends the use of virtual labs and animations to enhance students' understanding of nerve cells.

Are the ways of engaging with the world that students develop through higher education particular to bodies of knowledge they study? In this article, we examine how students' accounts of the discipline of chemistry in England and South Africa changed over the three years of their undergraduate degrees. Based on a longitudinal phenomenographic analysis of 105 interviews with 33 chemistry students over the course of their undergraduate degrees in four institutions, we constituted five qualitatively different ways of describing chemistry. These ranged from chemistry as something that happens when things are mixed in a laboratory to a more inclusive account that described chemistry as being able to explain molecular interactions in unfamiliar environments. Most students expressed more inclusive accounts of chemistry by the end of their degrees and the level of change appeared to be related to their educational experiences. In contrast to approaches that emphasise the generic student outcomes from higher education, these findings highlight the importance of recognising the distinctive outcomes that students gain from their engagement with particular bodies of disciplinary knowledge. It further highlights the importance of students understanding their degrees as an educational experience that requires them to commit to engaging with these bodies of knowledge.

The learning environment plays a crucial role in the promotion of school science. Redesigning the science classroom into a metacognitive learning environment is imperative in developing students' 21st century skills -- communication, collaboration, critical thinking and creative thinking. In this study, we exposed the students to a variety of metacognitive activities -- allowing them to plan, reflect, and evaluate their thinking skills and strategies. We intended to investigate the effectiveness of integrating metacognitive-enhanced and self-regulated learning strategies in understanding molecular genetics. We also explored and interpolated the roles of self-efficacy and metacognition in relation to their impact on Filipino students' scientific reasoning skills and conceptual understanding in the context of a Philippine science classroom. To establish a more comprehensive perspective, we applied the Plan-Do-Study-Act (PDSA) action research model, utilizing both quantitative and qualitative methods to find answers to the research problems. The results of the study highlighted the interconnectedness and interplay of science self-efficacy, metacognitive awareness, metacognitive-orientation of the classroom, and the scientific conceptual understanding of the students. These are crucial constructs in creating and maintaining a metacognitive orientation of the science classroom. The study also shows that science self-efficacy has a vital role in predicting the academic achievement of students.

In this paper, we describe a dynamic-model as a strategy to teach DNA transcription and translation in an active way. This activity aims to provide learning beyond memorisation through the simulation of molecular processes, stimulating the elaboration of questions and hypotheses by students. The dynamic consists of four steps, starting with different problem situations which provide a context and encouragement to start the activity. The next steps connect these problems with DNA transcription and translation, requiring the active participation of students to simulate these processes through a construction of a model based on an iron board and representations of cellular structures, enzymes and genetic sequences fixed in magnets. An implementation experience of this dynamic, applied to 21 undergraduate veterinary students at a public university in the city of Curitiba, Paraná State, Brazil, is also described. Data from pre and post-questionnaires suggest knowledge about DNA transcription and translation was improved and some previous mistakes were clarified. Among the positive aspects that were cited by the students, the words visualisation and playful were more frequent, which reflect the didactic aspects of the dynamic. Some points of attention are discussed throughout the paper, as well as educational implications associated with the material and its potential to promote active learning.

We present here two accessible ways for enhanced understanding of complex biological structures and their function in undergraduate Biology and Biochemistry classrooms. These methods can be applied for in-class instruction as well as for remote lessons, as they are cheap, easily available and easy to implement. LEGO® bricks and MERGE CUBE based augmented reality can be applied to make three-dimensional representation for any structure available on PDB. We envisage these techniques to be useful for students when visualizing simple stereochemical problems or complex pathway interactions.

Prospective preschool teachers (PPTs) need to have learning experiences with the practice of scientific modelling to be able to design appropriate lessons as teachers. In the literature on research in science education, scarce experiences of PPTs in scientific modelling can be found. This study aims to fill the knowledge gap about PPTs' representations of water and its states by means of models. To this end, an analysis is made of the models designed by PPTs and the difficulties they found in such a design process. The participants were 47 PPTs, working in groups of 2 or 3, forming 19 groups in total. The data source for analysis was the report written by each group. The oral presentation of these reports in class also served to clarify any doubts about the models elaborated by the PPTs. The models were analysed and categorized using qualitative content analysis methods, by combining inter- and intra-rater evaluation strategies. The results reveal that PPTs in general used a variety of resources to make models about the water molecule. Nonetheless, they found it harder to model the differences between the three aggregation states of water from a molecular perspective. The PPTs also acknowledged having had difficulties, such as when choosing and handling the materials they used to create the models or when thinking how to adapt them for the explanations to their peers. It is concluded with a discussion and implications of this study towards the PPTs' training in scientific modelling and its didactics.

Background: Nanotechnology, a multidisciplinary field with increasing societal importance, demands for an increase in research abilities and capacities. Yet, nanoscience and nanotechnology (NST) are largely inaccessible to K-12 students. This situation demands efforts in research towards bringing NST learning into K-12 classrooms. Purpose: The purpose of this study was to examine the outcomes of an application-based nanotechnology module, developed for late middle school students. The study focused on exploring student readiness to unpack unfamiliar NST concepts, and the effects engagement with NST had on student attitudes towards STEM subjects. Purpose: Participants included a total of three science teachers and 169, grade 8 and 9 students from two public school districts from a northeastern state of the USA over two years. Data was collected and used from students who consented for the study. Design and Methods: The NST learning module was developed in three phases, beginning with an introductory session to discuss module content and design. We then designed a module for implementation. Drawing from results from the pilot module and teacher inputs, we revised the pilot module for this study. Surveys, content questionnaires, student reflections, and classroom videos were collected for analysis. Results: Students demonstrated conceptual understanding of the working of the AFM after working closely with the tool. Our data highlights students' readiness to unpack unfamiliar NST concepts. Despite no significant changes, we noticed increases in students' attitudes towards STEM subjects and careers, and an increase in the number of students who plan to take advanced STEM courses. Conclusion: Based on our results, we suggest the use of technology-based experiences to introduce novel ideas of NST as early as eighth grade. The technology-based approach created a new space for contextualized learning. Working with teachers is critical to creating new teaching-learning experiences for K-12 learning, especially in the context of NST.

This study investigates students' cognitive resources for identifying symmetry elements using survey data collected from 39 inorganic chemistry students from twelve undergraduate inorganic classes at universities across the United States. We propose a framework that leverages students' knowledge of symmetry elements as a manifold of cognitive resources that can be productive or unproductive in certain contexts. This cognitive resources framework was paired with an asset-based perspective to advance work in this area beyond a deficit-framed study of ''correctness''. Herein, we present findings from a qualitative analysis of the rotation and reflection symmetry elements activated for students by four select molecules. Each molecule was presented in two different static orientations to determine the impact of orientation on students' cognitive resource activation. Our findings suggest that the orientation of static molecular images impacts the types of resources activated for students. Additionally, this study serves as an example for how to advance assessment of this topic beyond a binary approach (i.e. correct or incorrect).

Background: It is stated that it is necessary that students develop their nanoliteracy in order to come up with everyday issues arising from Nanoscale Science and Technology (NST) applications, taking informed decisions and estimating the potential risks and benefits. Even though the inclusion of NST in compulsory education is supported by many researchers, the research on students' preconceptions of NST concepts and phenomena is in its infancy. Purpose: We aim to identify students' preconceptions of (a) the conceptualization of size in the context of NST and (b) the explanation of the lotus effect (superhydrophobic materials). Sample: The participants of our research are 250: 5th and 6th grade primary school students in Greece. Design and methods: The data collection tool is a written questionnaire. Regarding the coding, both the inductive and deductive qualitative process is followed. Results: Concerning the concept of size, approximately half of the students are aware of non-visible objects. However, their classification of objects based on size is naive and based on vague criteria e.g. 'Large, Medium, Small objects'. For the lotus effect we identify three categories consisting of thirteen subcategories that reflect students' ideas about their macroscopic view of the lotus effect explanation. Conclusion: Students see the explanation of the lotus effect as a Direct process (explanations based on an identifiable causal agent). We argue that we could support them shift their explanations to the Emergent process (explanations based on non-identifiable causal agents) using appropriate tasks. Concerning the concept of size, students are aware of two main categories: the visible and nonvisible objects. We could help them create the macro-, micro- and nanoworld categories based on qualitative criteria.

To learn to read, the brain must repurpose neural systems for oral language and visual processing to mediate written language. We begin with a description of computational models for how alphabetic written language is processed. Next, we explain the roles of a dorsal sublexical system in the brain that relates print and speech, a ventral lexical system that develops the visual expertise for rapid orthographic processing at the word level, and the role of cognitive control networks that regulate attentional processes as children read. We then use studies of children, adult illiterates learning to read, and studies of poor readers involved in intervention, to demonstrate the plasticity of these neural networks in development and in relation to instruction. We provide a brief overview of the rapid increase in the field's understanding and technology for assessing genetic influence on reading. Family studies of twins have shown that reading skills are heritable, and molecular genetic studies have identified numerous regions of the genome that may harbor candidate genes for the heritability of reading. In selected families, reading impairment has been associated with major genetic effects, despite individual gene contributions across the broader population that appear to be small. Neural and genetic studies do not prescribe how children should be taught to read, but these studies have underscored the critical role of early intervention and ongoing support. These studies also have highlighted how structured instruction that facilitates access to the sublexical components of words is a critical part of training the brain to read.

Concept mapping remains widely used in education. However, little is known about how self-constructed concept maps and peer feedback can improve student learning outcomes in chemistry. We investigated the effects of peer feedback on concept mapping and how it improves students' learning performance in a large second-semester, introductory chemistry course. Three hundred and twenty students were randomly assigned to one of two concept mapping conditions: self-constructed concept map with peer feedback and self-constructed concept map without peer feedback. Each group constructed concept maps that depicted the relationship between concepts on the topic of intermolecular force. The results showed that students in the self-constructed concept map with peer feedback condition outperformed students in the no peer feedback condition in chemistry learning outcome. Overall, this study demonstrates that peer feedback enhances the effectiveness of learning with generative concept maps. The implications and future directions are discussed.

Recent progress in elucidating chemical reactions allows to explain chemistry by the potential energy of the involved chemical structures. Nevertheless, from an educational point of view, empirical results indicate that students often do not connect the core idea of energy with other chemical concepts. From a resource-oriented perspective, students do not draw on a coherent concept of chemistry to solve a problem but rather activate diverse cognitive resources, crucially depending on the context. It is thus of interest which resources high school students activate to reflect on energetic aspects of a chemical reaction. In this study, 38 German high school students in 16 focus groups were asked to explain kinetic and thermodynamic aspects of the reaction between hydrogen and chlorine. The unguided focus group phase and the following semistructured qualitative interview were analysed by qualitative content analysis. Results show that students have a diverse network of cognitive resources on energetic aspects. However, this network's structure seems to be dominated by terminology and a few prominent ideas such as activation energy. In contrast, students seldom drew connections between bond-making and energy release. Many students mainly argued on a macroscopic level and relied heavily on technical terms. If they argued on the sub-microscopic scale, however, they often focussed on the whole system rather than on specific molecules and their structure. Hence, students interpreted concepts like activation energy or reaction coordinate diagrams on the system level leading to unproductive reasoning. Overall, it seems that students seldom activate resources on molecular structures to argue about energetic changes in chemical reactions. Also, they rarely refer to the fundamental principle of energy minimisation to reason about the driving force of reactions. These results suggest that chemical reactions should be explained already in high schools on a molecular level providing a more explicit reference to energy as a function of chemical structures.

Australia-wide consensus was reached on seven core concepts of physiology. The "movement of substances" core concept with the descriptor "the movement of substances (ions or molecules) is a fundamental process that occurs at all levels of organization in the organism" was unpacked by a team of three Australian physiology educators from the Delphi Task Force into hierarchical levels. There were 10 themes and 23 subthemes arranged in a hierarchy, some 3 levels deep. Using a 5-point Likert scale, the unpacked core concept was then rated for level of importance for students to understand (ranging from 1 = Essential to 5 = Not Important) and level of difficulty for students (ranging from 1 = Very Difficult to 5 = Not Difficult) by the 23 physiology educators from different Australian universities, all with a broad range of teaching and curriculum experience. Survey data were analyzed using a one-way ANOVA to compare between and within concept themes. The main themes all were rated on average as important. There was a wide range of difficulty ratings and more variation for this concept compared with the other core concepts. This may in part be due to the physical forces such as gravity, electrochemistry, resistance, and thermodynamics that underpin this concept, which in themselves are inherently complex. Separation of concepts into subthemes can help prioritize learning activities and time spent on difficult concepts. Embedding of core concepts across curricula will allow commonality and consistency between programs of study and inform learning outcomes, assessment, and teaching and learning activities.