I found this today, haven't tried it yet, good luck everybody
1. Configurator is useless in reactivating a locked iPad. You will only be able to completely reformat the iPad using Configurator. If that’s ok with you, go for it – otherwise don’t waste your time trying to figure it out.
2. Open iTunes with the iPad disconnected.
3. Connect the iPad to the computer and wait for it to show up in the devices section in iTunes.
4. Click on the iPad name when it appears and you will be given the option to restore a backup or setup as a new iPad (since it is locked).
5. Click ‘Setup as new iPad’ and then click restore.
6. The iPad will start backing up before it does the full restore and sync. CANCEL THE BACKUP IMMEDIATELY. You do this by clicking the small x in the status window in iTunes.
7. When the backup cancels, it immediately starts syncing – cancel this as well using the same small x in the iTunes status window.
8. The first stage in the restore process unlocks the iPad, you are basically just cancelling out the restore process as soon as it reactivates the iPad.
If done correctly, you will experience no data loss and the result will be a reactivated iPad. I have now tried this with about 5 iPads that were locked identically by students and each time it worked like a charm.