If your iPad is disabled you will find the answer on how to get it working again in link below. Scroll down to the section that refers to "if you have previously synced your device with iTunes" or "if you have never synced your device with iTunes".
Also, I have included a link to restore from backup if one is located in iTunes as well as iCloud. Scroll down to the sections that refer to how to restore from backup.
iOS: Device disabled after entering wrong passcode
Using iPhone/iPad Recovery Mode
Saw this solution on another post about an iPad in a school enviroment. Might work on your iPad so you won't lose everything.
‘iPad is disabled’ fix without resetting using iTunes
Today I met my match with an iPad that had a passcode entered too many times, resulting in it displaying the message ‘iPad is disabled – Connect to iTunes’. This was a student iPad and since they use Notability for most of their work there was a chance that her files were not all backed up to the cloud. I really wanted to just re-activate the iPad instead of totally resetting it back to our default image.
I reached out to my PLN on Twitter and had some help from a few people through retweets and a couple of clarification tweets. I love that so many are willing to help out so quickly. Through this I also learned that I look like Lt. Riker from Star Trek (thanks @FillineMachine).
Through some trial and error (and a little sheer luck), I was able to reactivate the iPad without loosing any data. Note, this will only work on the computer it last synced with. Here’s how:
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.
Try it and good luck. You have nothing more to lose if it doesn't work for you.