Would Insight work if I have classrooms in different subnets?

This document is specific to Insight 9.0 and is maintained here for legacy purposes. Documentation for Insight 11 can be found here;

https://docs.faronics.com/faronics-insight/

Yes. The default option is IP-Broadcast which uses broadcast packets when the teacher needs to contact all student machines. Broadcast packets do not cross subnets or VLANs. If the teacher needs to cross a subnet or VLAN, using IP-Multicast or IP-Directed Broadcast are recommended.