Transforming an in-person course to an online teaching and learning environment is always challenging, especially if the course has a laboratory or studio component. As two co-instructors of a large introductory inquiry-based biology laboratory course with nearly 400 students enrolled, we faced such a challenge when our university switched to online instruction due to the COVID-19 pandemic in spring 2020. We had to plan for this transition wisely and consider the possible impact of our decisions on all the moving parts associated with such a large course. One of the available resources to our course was a group of undergraduate teaching assistants (UTAs), who had been assisting the laboratory instructors when classes met in person. The successful outcome of having UTAs during the spring semester and during an online summer course has encouraged us to share the lessons we learned from this experience here. As we move forward with online laboratory instruction in the future, we will rely on our UTAs in this relatively new learning environment. We believe that incorporating UTAs in online synchronous classrooms could help them gain valuable teaching and communication skills in such a developing learning environment. In addition, UTAs’ assistance can save instructors a great deal of time and reduce the pressure of teaching in and managing a virtual classroom, especially during a pandemic.