The phrase "to use a tripod" means to put a three-legged stand under a camera or other device to keep it steady and prevent shaking or movement while taking photos or recording videos. Full definition
The main culprits: not having your camera in focus or not using a tripod in low - light situations. (realtormag.realtor.org)
I would also suggest using a tripod for stability, and attaching a wide angle lens to increase the visibility of the whole class during recording. (sibme.com)
To answer you camera questions, yes I do use a tripod, pretty much always. (blog.fatfreevegan.com)