by Caroline Delaire, Civil and Environmental Engineering
Teaching Effectiveness Award Essay, 2014
I was the GSI for an upper-level undergraduate water chemistry course offered in Civil and Environmental Engineering. This class gives both undergraduate and graduate students a solid base to tackle all sorts of water pollution problems. The class is notoriously challenging because of the fast pace of the professor and the quantity of material covered. Most students don’t have a chemistry background, and some come from outside the College of Engineering. During my office hours and through students’ emails I quickly realized that the class generated a lot of anxiety. Students, undergraduate and graduate alike, were surprised and challenged by the quantity of equations and algebra involved in lectures and homeworks. I helped them the best I could with solving problem sets, but at the same time I started to understand that by focusing on algebra and equations students were at risk of missing the point of the class: gaining practical knowledge about water chemistry. They were simply not developing the intuition that would help them address real world environmental issues! Five years down the road, it doesn’t matter if students don’t remember how they solved question 2 of problem set 3. What matters is that they recall that water becomes less acidic when carbon dioxide escapes; that silver nanoparticles are much more toxic in the Bay than in the ocean because of salinity differences; that reducing conditions can lead to arsenic contamination of groundwater; that hot water pipes clog more easily with calcite than cold water pipes. Of course I wanted students to get to these conclusions through algebra, but more importantly, I wanted them to be able to anticipate the results.
“Intuition” became my motto and I designed discussion sections with the goal to develop students’ intuition. My sections were divided in two parts: a short quiz and problem sets. The fifteen-minute quiz covered the main take-home messages of that week’s lectures. It was online (on SurveyMonkey), and students used their smartphones, tablets, or laptops to answer the three or four multiple-choice questions. The quiz was anonymous, which mattered a lot for students. Importantly, the quiz involved no calculations and only required reasoning. I gave students five to ten minutes to submit their answers. Afterwards, I projected the answers on the screen, and we could all see the proportion of students who responded a, b, or c. Then of course I gave the solutions. I think the quiz was a big success because: (1) it was a great moment of active learning as everyone had to participate; (2) students’ answers allowed me to identify and focus on material that needed clarification; and (3) students realized that they could achieve a lot without any algebra or equation — in other words, that they were developing an intuition in water chemistry. During the second part of my sections, we covered one or two problem sets that I had come up with about real environmental issues, like mercury bioaccumulation in the Bay, fluoride removal from groundwater, or nitrogen recovery from urine. For students it was rewarding to see that they could apply their new knowledge to practical situations. I gave them handouts so that they could take notes properly and study these problem sets later at home.
After one month, I asked students to evaluate my sections and to share their opinion about quizzes and problem sets. I received very positive feedback. All respondents but one valued the quiz as a way to develop their intuition. Problem sets handouts were even more popular. Over the course of the semester, we started to see a decline in the number of wrong answers to quizzes. I think this is because sections helped students identify what they should take away from lectures, beyond algebra and equations.