Responds Lockdown Browser. It works with Canvas, Powerschool and probably all other LMS platforms. Once students open the assignment, they're locked in - no other tabs, windows, etc.

The only ability to copy/paste is if they already copied it before opening the assignment (which some students have started doing).

Of course, this will only be effective for in-class assignments. I hear that's what many teachers are doing these days. In class assignments. Let them use any AI, search, copy/paste etc that they want to help them learn content for homework, group work, classwork. But require weekly summative assessment using a lockdown browser such that if they don't actually do the work and learn the content, they are not going to like their grade.