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The high degree of complexity of macromolecular structure is extremely difficult for students to process. Students struggle to translate the simplified two-dimensional representations commonly used in biochemistry instruction to three-dimensional aspects crucial in understanding structure-property relationships. We designed four different physical models to address student understanding of electrostatics and noncovalent interactions and their relationship to macromolecular structure. In this study, we have tested these models in classroom settings to determine if these models are effective in engaging students at an appropriate level of difficulty and focusing student attention on the principles of electrostatic attractions. This article describes how to create these unique models for four targeted areas related to macromolecular structure: protein secondary structure, protein tertiary structure, membrane protein solubility, and DNA structure. We also provide evidence that merits their use in classroom settings based on the analysis of assembled models and a behavioral assessment of students enrolled in an introductory biochemistry course. By providing students with three-dimensional models that can be physically manipulated, barriers to understanding representations of these complex structures can be lowered and the focus shifted to addressing the foundational concepts behind these properties. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(6):491-500, 2017.

This paper describes a new approach for teaching general chemistry that combines lecture and laboratory into one seamless session and incorporates instructional methods supported by research-based findings. The results of a study that compared two instructional formats, conventional passive lecture and the student-centered, highly collaborative format known as cAcL2 (concept Advancement through chemistry Lab–Lecture), are also presented. Factors carefully controlled in this study include content material, time of day, time on task, and test format, scheduling, and grading. The results of the analysis of variance and the evaluation of the means conclude that the cAcL2 instructional method had a positive effect on student performance in an introductory chemistry class.

The importance of attitudes toward science has risen from widely accepted assumptions that achievement and attitude are positively interdependent and that affective variables are as important as cognitive variables in molding student learning. This report examines the effect on student attitudes toward learning chemistry in an active learning environment that has incorporated elements believed to positively influence student attitudes toward science including cooperative learning, hands-on activities, real-world applications, and engaging technology. These elements were considered for synergetic effects and not as individual contributors to the overall results. Two different sections of the same general chemistry course participated. The lecture setting was used as the control. Residualized gain scores were used to compare net changes in student attitudes. Data were analyzed for possible differences in gain for different academic majors. Anxiety in chemistry was monitored for the two class settings in three areas, learning in chemistry, chemistry evaluation, and chemical handling. Qualitative student feedback was also collected and is summarized in this report on the attitudinal aspects of instruction.

This experiment involves an esterification synthesis to study reaction kinetics where students explore these topics utilizing the sense of smell rather than the traditional approach of using spectroscopic methods. Students study the effects of various factors including the concentration of the carboxylic acid and the amounts of the catalyst or alcohols added. The kinetics in relation to the molecular structure is studied by changing the chain lengths and branching of alcohols or the carboxylic acids and inferring the effects on rates of the reaction from the rates of ester detection. Since many esters have naturally occurring aromas that are pleasant and easily recognized, this experiment studies esterification kinetics using the sense of smell to detect the emergence of the ester aroma formed during the reaction. Feedback from students strongly suggests their interest in the experiment as they discovered that their sense of smell could be used as an analytical tool.

Decades of research have demonstrated the correlation of spatial abilities to chemistry achievement and career selection. Nonetheless, reviews have highlighted the need and scarcity of explicit spatial instruction to promote spatial skills. Therefore, the goal of this literature review is to summarize what has been done during the past decade in chemistry and biochemistry education to promote spatial skills at the college level. In this review, we compare and contrast how these fields of study have used external representations and visualization tools in their instructional practices as well as the kinds of interventions and assessment efforts directed to promote and evaluate spatial skills. Our findings show that explicit instruction to promote spatial skills has been on the rise but not at the level of other cognitive skills. Therefore, implications for teaching and potential areas for investigation are suggested.

This laboratory experiment uses the sense of smell to determine end points of acid–base titrations. Olfactory indicators include garlic, onions, and vanillin. Results show that garlic and vanillin gave the most accurate results when calculated NaOH molarities were compared to the standardized values. These olfactory indicators in acid–base titrations gave consistent results when tested by a diverse student population. The preparation times, cost, and safety issues are comparable to traditional titration experiments. In addition to olfactory determinations, the intrinsic pigments in yellow and red onions were tested as complementary visual indicators and compared to commercial indicators added to white onion solutions. All students, including those with visual impairments, may perform these olfactory titrations and the level of instruction can be expanded from a phenomenological point to the complex aroma chemistry behind the scenes. These experiments can also educate the nondisabled student and change attitudes toward disabled partners.

Three physical model systems have been developed to help students deconstruct the visualization needed when learning symmetry and group theory. The systems provide students with physical and visual frames of reference to facilitate the complex visualization involved in symmetry concepts. The permanent reflection plane demonstration presents an explicit example of a reflection plane and provides visual indicators that students use to support or invalidate the presence of a reflection plane. The 3-D coordinate axis system provides an environment that allows students to envision symmetry operations beyond the basic geometry of bonds in a relevant molecular context while the proper rotation axis system is designed to provide a physical frame of reference to showcase multiple symmetry elements that students must identify in a molecular model. The 3-D coordinate axis and the proper rotation axis systems allow students to incorporate their own molecular modeling kits. All three model systems have corresponding worksheets designed after a modeling framework that takes into consideration three basic principles in "viewing" visualization as a problem solving tool: deconstruction, comparisons, and reuse of strategies.