Tips for a First-Time Teaching Assistant

For the last 3 years, I’ve been teaching the lab sections as a teaching assistant for the statistics sequence at the Johns Hopkins Bloomberg School of Public Health. The course is geared towards master’s level students in public health, though some PhD students and doctors/members of the JHU Medicine community also take it. As you can imagine, there can be a range of familiarity in the classroom with regard to what students know about stats, math, and coding.

I remember being quite nervous when I first started teaching, not knowing what to expect. So I wanted to share a few tips today about being a TA, specifically one teaching a mostly lecture-based lab, based on my experience.

  1. Remember to take ownership of the class - As the lab instructor, there is an expectation in the classroom1 that you lead the environment. It may sound obvious, but you are responsible for starting the class and dismissing the class. This may take a little getting used to if you haven’t taught before.2 Taking ownership of the class also means that you do need to sound confident about what you are saying or students may start losing trust in you as a teacher. The good news is that students usually enter the classroom with faith in you3 and prepping the material beforehand should mostly take care of your confidence in teaching the course content. To be clear, it’s OK to say you don’t know the answer to a question – this will almost inevitably happen at some point and students will likely just take it in stride, so it’s not as big a deal as you may fear. Being honest is better than the alternative of making stuff up and you can always say you’ll get back to their question after lecture or follow-up with them later.

  2. Repeat what you say multiple times - The field of statistics has a lot of jargon that can be confusing for students who are encountering them for the first time. Therefore, especially when you are introducing new concepts and terms, it’s good to repeat definitions and use them in different contexts/ways so that students have multiple times to grasp what they mean. There may be lots of other reasons why students didn’t hear you the first time (maybe they were distracted, busy copying down notes, or still thinking about a previous section). One way to gauge whether students are following4 is to pay attention to the types of questions they’re asking. For example, if there are a lot of clarifying questions about basic things, then you might have gone through the material too quickly.5

  3. Pause for questions - One thing I’ve noticed is that questions from students often exhibit a “snowball effect.” That is, after one student asks a question, many more students feel comfortable asking questions too. To increase the probability that at least one student will break the ice, I recommend deliberately pausing at points throughout the lecture and/or explicitly asking them if they have questions. Not all students are necessarily comfortable interrupting you mid-sentence, so creating that intentional space for questions can be helpful to encourage discussion.

  4. Play to your strengths - When I first started teaching, I felt some self-imposed pressure to be the ideal teacher I had imagined in my head, e.g. a funny instructor who was full of energy and bantered with students. But later, I realized that while those are great traits to have, they’re not necessary to be a successful teacher. Personally, I’m not an outgoing personality by nature, but I do have other strengths that come more easily to me. For example, what some students have told me is that they appreciated the clarity and conciseness in my lab sessions. Different types of instructors will appeal to different students and so there are more ways than one to be a “good” teacher.

I hope this post alleviated some of your qualms and remember that you don’t have to get everything right the first (or second or third) time. You’ll figure out what works best as you continue to teach and gain more experience.


  1. Or Zoom session!↩︎

  2. I personally found it to be a rather strange experience the first few times.↩︎

  3. This may be context-dependent. If as a PhD student, you are the lead instructor for the course, then students may start off being more skeptical than they would be for a professor and you’ll have to do more to earn their trust.↩︎

  4. Other than directly asking them, which they may not be 100% honest about, since it puts an explicit burden on the student to admit that they didn’t understand.↩︎

  5. It’s true, however, that no matter how many times you explain, a few students might not be able to understand what you’re saying at that time. In that case, you may have to redirect them to review the material in their own time and move on for the rest of the class.↩︎