UThere isn't technically a limit to how many students you can have in an individual section. However, we recommend limiting sections to 40 students or less to ensure that our teacher tools remain user friendly.
We also recommend that you create a section for each class period that you are teaching.
Locking Student Enrollment
You can lock student enrollment for your section by toggling Lock Enrollment on in your Section Settings:
Click the three dots next to the section
Select Edit Section
Scroll down to Lock Enrollment and toggle the button