Does the software spy on students 24×7?

No. The software can take screenshots during a teacher session but if the student or teacher exit the joinIN session then the student device is no longer available

Can the software interfere with operating system?

No. The software only runs at the user level and does not attempt to modify any system settings

Is my data being sent out to the cloud?

No. A license ticket is checked on the teacher computer and the rest of the data stays on the school network. 

Is my data safe on your servers?

Yes. Any identifiable information e.g. email addresses is encrypted 

Can I run it on computer labs instead of BYOD ?

Yes. There is a method to install the software in a lab mode. Once done the teacher software can grab the computers from that lab.

I only want to use it for some students. Do I need a license for all of them?

No. You can license it per teacher and use it as you see fit.