Just wondering: would refurbished core-duo Thinkpads with something like neverware's ChromeOS on them be a better way forward for a cash strapped school?

Cheap to buy, the machines have survived N years so by a Darwinian process any clunkers have been removed from the pool and they are built to a decent standard to start with. ChromeOS would imply cloud storage so students don't lose work &c. Depends on the use cases I imagine.