Windows 2012R2 as RDSH and rollback to clean state

Question

I am in the process of installing a new Windows 2012R2 server in Remote Desktop Session Host mode that will work as a "terminal server" inside a classroom.
The idea then is that after the server is set and ready to install applications, I get a 'snapshot' (or call it whatever you like), I install the software needed for a specific course, let people to connect and when the course is finished (after some weeks) I rollback to the initial snapshot to have a clean state where to start from for the next course.

Any idea how to get this? I thought and read about some solutions but I wanted also ask people their opinion:

1. virtualize the RDSH server and manage its snapshots from the HyperV, reverting each time when needed
2. create a VHD of the initial system (phys2VHD ??) and booting from that integrating differential VHDs each time
3. using WindowsBackup and Restore (but seems to keep the files for new installed apps)
4. using thirdy part software such DeepFreeze, Timewiz, RollbackRX, etc..
5. ???

for the above I have some doubts:
how to integrate the patches/updates in the middle of a snapshot? would it be possible to recover without being physically on the server (which is a pain)?

Thanks for any answer!