In a classroom environment there will be a Zoom Room and teacher/students in the meeting on laptops. When they speak through the laptop it comes out of the Zoom Room and causes an audio loop when the laptop picks it up.
The ability for the Host to assign users to a Zoom Room. Their voices will not come out of the Zoom Room or laptops causing the audio loop.
Generally the teacher and students have to mute their laptops speakers and microphones.
For the use in very large classrooms with constantly moving desks. Even the $6k ceiling microphone don’t sound as good as a microphone in front of a student.