I gave my second lecture for my practicum in EOSC 110, which is a core 100-level geoscience course on the Earth’s origin, composition, structure, and natural resources. This is a large class of over 200 students, making it a stark contrast to my first lecture that was a smaller class of only 40 students. This was an intentional choice on my part to ensure that I gained experience in a variety of class sizes.
This lesson was particularly challenging for me because it was on a subject that I’m not very comfortable with and struggled with when I learned about it during my own undergraduate degree: geophysics, specifically the structure of the Earth’s interior and its magnetic field. Therefore my knowledge of the material before I started preparing for the lecture was probably not that far above that of the students, and I had certainly not attained the level of an expert by the time I delivered the lesson. I hope that this worked to my advantage in that I avoided some expert blind-spots that I may have fallen into in a subject that I was more familiar with.
I think the biggest challenge for me during this lesson was trying to juggle the use of a PowerPoint, iClicker software, and YouTube videos, all while trying to keep 200+ students engaged. In the very first part of the lesson, I was so focused on not forgetting any of the content I had to deliver that I missed opportunities to ask the class questions as I went along. Later in the lesson, when I started asking more questions I had a lot of trouble getting students to answer them. This may have been because I hadn’t starting asking questions and encouraging student participation from the very beginning. That being said, something that I think I did particularly well in this lesson was to not back down when I didn’t immediately get a student volunteer to answer my question. Instead I just continued to look around the room, even though it sometimes felt like minutes had gone by since I first asked the question, and eventually a student would raise their hand. As I progressed through the lesson I started trying new ways to get students to answer questions, such as by specifically asking someone from the back of the room to answer. If these were students that I was more familiar with and had been teaching for longer, I may have resorted to calling on a student, but I wasn’t comfortable doing that with a new group of students.
At one point during the lesson a student answered one of my questions with an explanation that I didn’t fully understand, and that in my mind seemed overly complicated to explain the concept. I was tripped up by his answer and felt that if I didn’t completely understand it then it was likely that at least one other person in the class was also confused and was looking for an alternative explanation. This prompted me to ask the class for an alternative, simpler explanation of the same concept. After doing this I realized that it may have made the first student feel like their answer wasn’t adequate enough, even though they were correct, and that they may have felt embarrassed. I mentioned this to my mentor in our meeting and he said he knows the student and highly doubted that the student was affected by it. Regardless, I think this situation was a good reminder to always put myself in the students’ place and I’ll make sure to remember it in the future.
I ended the class with an activity that tied the two parts of the lesson together by comparing the structure Earth to other planets and relating that to their magnetic fields, or lack thereof. This gave students the chance to apply what they’d learned during the lesson and to integrate their knowledge of both concepts. I left enough time at the end of the lesson for all students to complete the activity and hand it in at the end. This was something that I had worried about because I thought I might have too much content for the allotted time.
In my meeting with my mentor, he said that my lesson went really well, especially since it was only my second time teaching a large class (and third lesson given on my own). He said that I had a good tone of voice and pace, and that he liked how I tried to try to make small jokes to make students feel more comfortable. Although that was unintentional and usually happened because of my nerves, I’m glad that he thought they had a positive outcome. The main thing I have to work on are the details of how I administer clicker questions.
Some things that my mentor mentioned were that I often gave 45-60 seconds to answer a question, whereas he suggested that 25-30 seconds is sufficient. This is because students will often “race” to submit their answers when you give them a 5 second warning, regardless of how long the poll was open for. Also, at the beginning of the lesson I got students to pair up and discuss their answers after all the clicker questions, telling them to “turn to your neighbour and convince them that you are right”, and then re-vote on the answer. I’d actually decided to do this because in the lecture of his that I observed I noticed that he told students to discuss their answers after each clicker question. It turns out in all those cases not a high enough number of students had gotten the answer right, so discussions were needed. He suggested only having a discussion when <60-70% of students got the right answer. Having a discussion after every question risks that clicker questions will start to seem redundant, and that students may start thinking they’re a waste of time. To justify the need for discussion when students perform poorly on a question, he suggested I could explain why a discussion is needed by saying things like, “There was a really good split between answers for this question so discuss it with your neighbour and vote again”, or, “A lot of you could benefit from a discussion of this question”. Finally, he suggested ways to get students to volunteer to explain why they voted for a certain answer to a question. Instead of trying to ask someone that chose the wrong answer to explain their reasoning (which is very unlikely to happen in front of the whole class) I could say things like, “Why do you think someone chose this answer?”. Then even someone who got the right answer could volunteer to explain why someone might choose another answer. If this still doesn’t work to get a volunteer, I could instead ask them to discuss my question with their neighbour.
Overall, I think this lesson was a great experience for me to practice teaching large class sizes. For my next lesson using clickers, I am confident that I will be able to use the new techniques I learned so that I can use them more effectively and ensure that students see the value in clicker questions.