Something new: Lab-based performance assessments
Posted by Melissa on February 10, 2012
For all kinds of reasons, this has been one of my most brutal terms at Carleton. On the teaching front, I have a new prep, electronics. I loved electronics as a student, and I’m thoroughly enjoying the opportunity to delve into the material again. I also decided that I wanted to try out a couple of new (to me) pedagogical strategies in this course, which means that I stacked the extra work of exploring new teaching techniques on top of the extra work of a new prep. One of the things I’ve done in this course is to jettison traditional quizzes for lab-based performance assessments. The idea is that electronics is most useful if you both understand the theory and can apply that theory to build interesting/useful circuits. Traditional quizzes assess theoretical understanding, but do little to assess how well a student grasps the hands-on aspects of things, including troubleshooting.
As a student, my electronics course included a couple of lab quizzes. As a teacher, I’d never tried giving lab quizzes before this term, and I wasn’t sure how to approach these. However, with a bit of a push from former colleague Kris Wedding-Crowell, who had tried lab quizzes in the contemporary experimental physics course, and from Scott Seagroves, the lab instructor at the College of St Scholastica, I decided to take the plunge and try lab-based performance assessments. Now in the midst of administering my second one this term, I’m glad I took the risk.
How does a typical performance assesment work? I give the students the schematics for a circuit, and ask them to make predictions about several aspects of its behavior, or what might happen if a component fails open or shorted. Once the student has done the theoretical work and come up with predicted values, I ask the student to go to lab, build the circuit on the breadboard, and test their predictions. If there are discrepancies, the student can either try reworking the theoretical prediction or reconfiguring the experimental set-up. The benefit of this approach is that I get a good sense of what students understood and where they have trouble. It feels like a much more authentic assessment of what we do in the class, equally weighting theoretical understanding with practical know-how. The downside? Scheduling all 15 students to take the assessments requires a lot of time because I have to be present in the lab to watch as they build and test their circuits. Since time is a particularly scarce commodity this term, this is a significant drawback. Nevertheless, I have once again been reminded that jumping out of my teaching comfort zone, while scary and demanding, can be rewarding, and it keeps me growing and learning as a teacher.