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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.

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.

Laboratories play a crucial role in the undergraduate science curriculum and the effectiveness of learning in laboratories is influenced by learners' interactions with other students, the instructors, and the equipment used. In this study, a pre-lab survey was used to collect information about students' expectations of interactions in chemistry laboratories and how they can be ranked according to their importance. Post-lab surveys were used to capture students' perspectives about the frequency of interactions that existed in laboratory sessions they had completed. Direct observations of some laboratories were also conducted principally to validate students' self-reported interactions. The data were also sorted by three levels of student achievement in order to relate students' expectations of the importance of different interactions (pre-lab survey) and their self-reported frequency of interactions (post-lab survey) with their laboratory grades. Results from the pre-lab survey showed that student-instructor interactions were anticipated to be the most important ahead of conducting the laboratory activity, whereas results from the post-lab surveys showed that the most frequent interactions occurred between students. Students' self-reports (post-lab survey) and the direct observations agreed well suggesting that the post-lab survey is a robust tool for capturing the frequencies of student interactions in this and future studies. The results also showed that students gaining high grades both anticipated the importance of, and then engaged more frequently in, two-way communications with both students and instructors whereas students with lower grades placed a relatively higher reliance upon passive interactions such as the pre-lab briefing, the laboratory manual and internet sources. Finally, recommendations are offered to curriculum designers, instructors and students based on the overall findings of the study.

This one-semester, mixed methods study underpinning social cognition and theory of planned behaviour investigated the attitudes, self-efficacy, and experiences of 559 first year undergraduate chemistry students from two cohorts in modified process-oriented guided inquiry learning (POGIL) classes. Versions of attitude toward the study of chemistry (ASCI v2), and chemistry attitudes and experiences questionnaire (CAEQ) were adopted, modified, and administered to understand and gauge students' affective outcomes before (pre) and after (post) POGIL intervention. Students' post-POGIL perceptions of their attitudes, self-efficacy and experiences were statistically significantly higher. In addition to confirmatory testing of reliability of data obtained from ASCI v2 and CAEQ in an Australian POGIL context, the findings suggest that POGIL intervention provides positive affective experiences to students who are new to chemistry or have limited prior chemistry knowledge.

Pedagogical practitioners who emphasise active learning in undergraduate chemistry courses widely use the Student Assessment of Learning Gains (SALG) instrument to measure students' perceptions of their gains in knowledge and skills in chemistry. Although numerous studies have reported SALG results in support of successful pedagogical interventions, a comprehensive construct-verified version measuring students' perceptions of their chemistry learning is lacking. This paper aims to identify latent constructs of the SALG instrument that was administered in Process Oriented Guided Inquiry Learning (POGIL) classes by using exploratory and confirmatory factor analyses. When the SALG was administered on two separate occasions with two different groups of students following four weeks of instruction on topics in stereochemistry, the results revealed a four-factor structure consisting of 32 items that included Active Learning, Concept Learning, Resources, and Process Skills. These findings demonstrate an approach to collect evidence to support the match between intended constructs and measured variables in light of a targeted pedagogical intervention.

This study focused on the attitude of tertiary students, in a science discipline, towards completing collaborative learning tasks. Two samples of students, enrolled in different units across different tertiary institutions, were considered. Students in sample 1 were required to work in small groups to produce an information poster on an allocated chemistry topic. Students in sample 2 were given the task of producing a short iMovie on a science topic of their choice. A mixed methods approach was used to collect attitudinal data from students via pre- and post-surveys. Data collected were interpreted within the context of six key factors drawn from the literature on collaborative learning: level of interest in the task; familiarity with other group members; level of contact (related to the assignment) for completion of the task; strategy used to complete the task; student's self-evaluation of their group's effectiveness and overall opinions on the use of collaborative learning tasks in science at a tertiary level. Student comments indicate that most considered these collaborative learning tasks a positive and motivating experience. Written open-response questions indicate that students recognize the importance of developing strong interpersonal skills during their tertiary studies, to enhance future employment prospects, and felt completion of a small group-based activity had contributed to the development of these. This study confirms that students highly value the use of collaborative learning tasks that provide an authentic learning experience and opportunity to learn subject matter in a relevant context. (Contains 2 tables and 2 figures.)

In chemical kinetics, in addition to the concepts related to kinetics, stoichiometry, chemical equilibrium and the characteristics of the reactants are often involved when comparing the rates of different reactions, making such comparisons very challenging for students at all levels, as well as for pre-service science teachers. Consequently, four multiple-choice items were developed to determine the understanding of 217 pre-service science teachers of the kinetics of acid reactions that are taught at the Grade 9 to 10 levels in Singapore schools. Each of four items compared two different acid reactions under similar conditions, and respondents were required to select the best graphical representation for the two reactions. Respondents were also required to provide reasons to explain their particular selection for each item. In addition, one item on the dissociation of sulfuric acid and two items involving excess/limiting reagents were also included to provide additional data on the pre-service teachers' understanding of these concepts that were assessed in the four items on kinetics of acid reactions. The results showed that the pre-service teachers had difficulties in explaining the properties of different common acids, including the dissociation of the acids and how these affect the rates of the different acid reactions. This study highlights the importance of determining pre-service teachers' understanding of the concepts that they will be teaching with a view to addressing areas of difficulty, as these will have consequences on their future students' learning. (Contains 4 tables and 14 figures.)