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The "Next Generation Science Standards" identifies argumentation as a central practice, and, subsequently, energizes teachers to develop students' capacity to write well-reasoned arguments and support their claims with relevant evidence. These skills now expected in the science classroom have long been central to instruction in English-language arts. This article overviews the design and delivery of a first-time interdisciplinary collaboration between three teachers, representing English language arts, science, and a teacher-librarian. Their integrated unit was based on principles of scientific argumentation. Recounting the experience from the perspectives of the teachers, and informed by observations and interviews conducted, discussion centers on the practical aspects of unit delivery and meeting intended goals. This article thematically explores qualitative data collected from the teachers, including individual reflections and a focus group interview, as well as classroom observation and student post-unit survey data. Drawing on the experience from the inaugural implementation, we discuss considerations for future efforts and implications for the broader audience.

In this activity, science education and modern technology are bridged to teach students at the high school and undergraduate levels about protein folding and to strengthen their model building skills. Students are guided from a textbook picture of a protein as a rigid crystal structure to a more realistic view: proteins are highly dynamic biological molecules in the heterogeneous environment inside the living cell. Simple mechanical models and computer simulations that evolve in their complexity as the instruction progresses are at the core of this lesson. Methods of statistics and physical chemistry (thermodynamics and kinetics) are employed to investigate a flexible version of a peptide that can sample various conformations within the folded ensemble and ultimately unfold into a random coil.

The microsecond folder lambda6-85 is a small (9.2 kDa = 9200 amu) five helix bundle protein. We investigated the stability of lambda6-85 in two different low-fluorescence crowding matrices: the large 70 kDa carbohydrate Ficoll 70, and the small 14 kDa thermophilic protein SubL. The same thermal stability of secondary structure was measured by circular dichroism in aqueous buffer, and at a crowding fraction phi = 15 +/- 1% of Ficoll 70. Tryptophan fluorescence detection (probing a tertiary contact) yielded the same thermal stability in Ficoll, but 4 degrees C lower in aqueous buffer. Temperature-jump kinetics revealed that the relaxation rate, corrected for bulk viscosity, was very similar in Ficoll and in aqueous buffer. Thus viscosity, hydrodynamics and crowding seem to compensate one another. However, a new fast phase was observed in Ficoll, attributed to crowding-induced downhill folding. We also measured the stability of lambda6-85 in phi = 14 +/- 1% SubL, which acts as a smaller more rigid crowder. Significantly greater stabilization (7 to 13 degrees C depending on probe) was observed than in the Ficoll matrix. The results highlight the importance of crowding agent choice for studies of small, fast-folding proteins amenable to comparison with molecular dynamics simulations.