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ABSTRACT Those involved in STEM outreach, from elementary schools through undergraduate students, all use varying teaching styles in an effort to instruct and inspire students. However, it is incredibly difficult to gauge or compare learning outcomes from new teaching techniques in situ. In this work, we describe the outcomes of a new undergraduate mini-course at Johns Hopkins University, Chocolate: An Introduction to Materials Science. In particular, the outcomes of teaching binary phase diagrams in this course using topical food examples were compared to the outcomes of the same instructor teaching a similar control group of students using standard textbook examples, reducing a number of confounding factors and allowing us to objectively analyze the benefits of using an atypical, popular approach to teach a standard subject. Results indicate that the students in the Chocolate course were not only more excited and engaged in the lecture, but they had identical or potentially greater learning gains than the control group. 

We summarize our recent results on material, device, and circuit structures for detection of volatile analytes in the atmosphere and proteins in aqueous solution. Common to both types of sensing goals is the design of materials that respond more strongly to analytes of interest than to likely interferents, and the use of chemical and electronic amplification methods to increase the ratio of the desired responses to the drift (signal/noise ratio). Printable materials, especially polymers, are emphasized. Furthermore, the use of multiple sensing elements, typically field-effect transistors, increases the selectivity of the information, either by narrowing the classes of compounds providing the responses, distinguishing time-dependent from dose-dependent responses, and increasing the ratio of analyte responses to environmental drifts. To increase the stability of systems used to detect analytes in solution, we sometimes separate the sensing surface from the output device in an arrangement known as a remote gate. We show that the output device may be an organic-based or a silicon-based transistor, and can respond to electrochemical potential changes at the sensing surface arising from a variety of chemical interactions.