Aloha Captain.
I was only on my second cup of coffee when I first answered and some more solutions came to mind.
First make some room on your iPad then install the DropBox app (link belowl). DropBox is a free cloud storage site. Once you upload your photos even if you delete all your photos from your iPad and delete the DropBox app your photos are still safe at the DropBox site. It's sort of like photo insurance.
Second make sure you have iCloud turned on and are making a automatic iCloud backup every night. Now should the school officials complain about the number of photos you have and don't believe you it's a erroneous reading hand them your iPad a say it's recommened the only thing that might help is to erase the iPad and restore from your iCloud backup. I'll bet they hand you your iPad right back.
Remember there are no hidden photos. If they're not in the Photos app they're not on your iPad.
Stay well. Bob.
Dropbox by Dropbox
https://appsto.re/us/63ZHt.i