My actions as a teaching assistant for a large introductory chemistry course are nuanced. At a large research-intensive university in the Midwest, teaching a large number of students (~2800 students in the fall semester, ~1600 in the spring semester) presents constraints that highly dictate our interactions with our students and fellow teachers. Three instructors spend most of their time interacting with students by lecturing at them; more specifically, I would classify their actions as either telling truths, positing questions, or sitting in silence.

Any epistemic uncertainty appears in the ‘sitting in silence’ portion of class. This occurs after instructors ‘pose questions’ questions to students. The epistemic uncertainty quickly disappears when instructors begin ‘telling truths,’ which takes up the majority of lecture time.

Graduate students act as teaching assistants by interacting with students during the lecture. They also interact within the smaller discussion sections that teaching assistants lead. These sections meet once a week and hold 20~30 students. Class starts with the teaching assistant explaining what particular content students will be talking about. The purpose of the small discussion sections is to give students time to answer questions. The session begins with an exposition given by the teaching assistant informing students what content the session will include, and possible reminders of the content covered in lecture.

Students then work in groups of three answering questions and recording their answers on a worksheet. As students work, teaching assistants pose and answer student questions. Often in my interactions with students, I sit in silence after I have asked students questions, allowing time to think and for other group members to chime in. Any further information provided by the student is recognized verbally and either confirmed or challenged with questions. If a group of students have not been satisfied with my questions, I may leave them to ponder or directly challenge their misconceptions. I make sure to validate students’ previous answers despite their inaccuracy and point them towards the appropriate section in the course notes.

In my opinion, this mechanism of learning follows from the misconception theory of conceptual change. Perhaps we instructors place to much emphasis on cognitive conflict and do not bring in students’ prior conceptions enough. However, those prior conceptions can be counter intuitive in chemistry or physics. Researchers have spent a significant amount of time categorizing student misconceptions. Understanding where students struggle is helpful when attempting to answer student questions, I believe this is what some refer to as pedagogical content knowledge. How helpful is this in my day-to-day interactions with students? I know what explanations make intuitive sense to my students and I know what explanations Insite confusion instead of understanding. This understanding effects the vocabulary I use in class. It affects what I say to students, but it does not alter the main mechanism for learning.

JLS