Nobody seems to be complaining about the fact "thin-clients" based on VNC, are not for what most people do at work, they were originally conceived so that server-admins could become more efficient by not needing to move or incur call-out-charges for companies.
For schools (as productivity is not the goal), the benefits as I see it are
* Fits in with existing infrastructure
* Allows central storage of student work (assuming they have to login to their student account)
* Pre-packaged (setup is an issue with hobby kits like rPi)
Problems will come from kids opening & switching memory cards, breaking out of VNC and altering the Pi (which likely hasn't been secured). Also if it's for displaying windows, how will the students use their GPIO? You need an alternative where you lock down the Pi, enable access to it's GPIO etc, but upload files to, and retreive files from the central server (maybe via AD).
Andrew Mulholland @gbaman has gone some way towards what is needed, so maybe they can buy some of his time, contribute to his project PiNet and move from central computing to easy-setup labs Pi's for students.
Biting the hand that feeds IT
