I am about to embark on a PI/Arduino adventure.
At this stage (ending further information), it looks like I am going to have a crack at using PiNet (http://pinet.org.uk/) using an old widows based server with a virtual Ubuntu machine. This system seems to have heaps of advantaged over a one card/one student policy and also comes with the need for me to now become some sort of admin as this work is not in scope for our standard IT folks.
Just wondering how others have gone with networking in a classroom environment and how they have managed to multPi (you heard that word first here).