Sounds like a good way to make use of old eMachines, at a large discount too.
Finally, the year of the Linux Desktop! (eMachine edition)
I had an exact machine like this, with these specs, just with an internal Nvidia GPU and 4 extra video cards added. Using USB splitters and USB audio cards, we made that computer work for 5 users simultaneously.
Built software for initial setup (what USB mouse and KB goes with what monitor?) and it worked like a charm.
There was even enough ram available to run a single virtual box instance with Windows XP (I believe) for one single user.
The Linux desktop was skinned to look like Windows XP too and for class rooms we used... I forgot the name, some open source classroom management system where the teacher could guide students remotely
Linux is awesome