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This dissertation contains findings from two research projects. The first research area focused on assessing engineering students problem solving skills. Problem solving related to two material and energy balance topics – vapor liquid equilibrium and reacting systems with recycle - were examined first followed by a more holistic analysis across two cohorts. Research employed a pseudo-control/treatment design across two cohorts to examine impacts of replacing Textbook problems with student-written, video-inspired (YouTube) problems. The Treatment group completed both YouTube and Textbook problems, while the Control group completed only Textbook problems. Problem solving skills was assessed with an established rubric modified by the research team. Also, the NASA Task Load Index survey quantified the difficulty of homework problems. For each cohort, findings were drawn from 9 YouTube problems and 10 textbook problems, ~2000 task-load surveys and ~2500 problem solving scores compiled by multiple raters. Each of Treatment and Control groups were compared across cohorts to verify outcomes. In general, students displayed higher problem solving on YouTube problems compared to Textbook problems. Students perceived YouTube problems to be of statistically similar difficulty as Textbook problems. The Treatment group showed improvements in problem solving (effect size: Hedges g = 0.1 to 0.6), which was verified across two cohorts.The second research area developed a recently patented anion exchange membrane intended for use in electrochemical devices. The chemistry, processing, and characterization of anion exchange membranes, created by crosslinking a commercially available polyelectrolyte, poly (acrylamide-co-diallyldimethylammonium chloride), with glutaraldehyde, were studied. Crosslinking was confirmed through Fourier-transform infrared spectroscopy by the presence of a new C=N bonds. The influence of four parameters to optimize AEM properties: crosslinker/polyelectrolyte mole ratios, polyelectrolyte concentrations, drying temperature, and drying time of AEMs were examined. In addition to physical and chemical characterization, mechanical properties under both wet and dry conditions, including strength at break, Young’s modulus, and elongation, were measured using an extensional rheometer tool and custom-built humidity oven. AEMs were ~30 microns thickness, which is important for lowering the resistance for ion transport and should result in higher ionic conductivity. As hypothesized, increases crosslinker to polyelectrolyte ratio decreased water uptake, IEC, and conductivity. In addition, improved alkaline stability and mechanical strength at wet conditions were found in membranes with larger crosslinker to polyelectrolyte ratios. Next, increased polyelectrolyte concentration did not show a strong relationship with strength at break of AEMs, disproving the hypothesis that higher polyelectrolyte concentrations having many entanglements would improve mechanical properties. Overall, AEMs with encouraging properties were created, including water uptake

Problem solving is a signature skill of engineers. Here, problem solving is employed when students apply course concepts to reverse engineer YouTube videos and solve new student-written, homework-style problems (YouTube problems). Replacing textbook problems with YouTube problems, this research focuses on examining the rigor of YouTube problems as well as students’ problem-solving skills on textbook and YouTube problems. A quasi-experimental, treatment/control group design was employed, and data was collected and evaluated using multiple instruments. First, rigor of homework problems was examined using the NASA Task Load Index. Also, problem solving was assessed using a previously-developed rubric called PROCESS: Problem definition, Representing the problem, Organizing the information, Calculations, Evaluating the solution, Solution communication, and Self-assessment. PROCESS was modified to independently measure completeness and accuracy of student responses, as well as identify errors committed in material and energy balances. In the treatment group, students were assigned ten textbook problems and nine YouTube problems. In addition to obtaining an evidence-based assessment of problem solving via PROCESS, students’ learning attitudes, overall and with respect to problem solving, were measured via a self-reported survey known as Colorado Learning Attitudes about Science Survey (CLASS). Utilizing YouTube problems in classroom did not influence learning attitudes of students negatively. Students reported that YouTube problems possessed similar rigor as Textbook problems. Instead, students solving YouTube problems measured small effect size improvement in problem-solving skills.