Yes, get a variety pack or two until you know what you’re doing with the machine.
No… Easel will be fine to get you started and there’s plenty of free options for many other tools.
Yes. Depends on the program/goals.
Possibly if I have more information. Type of school? Type of setting? Staffing? Etc.
I am a STEM teacher in a public middle school. We have a Carvey in the classroom.