What to do with an old iPad
Short answer: Not much.
Longer answer: Don't buy any locked devices, not even as gifts.
I ended up with the iPad2 I gave my Dad in 2012. He loved gadgets. I picked the iPad since he already had an iPhone and I didn't want to add to my tech support burden, his Windows laptop was regularly rebuilt due to infestations of malware from random things he installed or just running as Administrator and web browsing. I wanted him to have something nice but convenient (for both of us). He took excellent care of the it. He kept it in a case and there's only a single mark on it, the screen is perfect. The battery still holds a solid charge. I did a factory reset and it should be good to go.
There's a hitch: Apple dropped support for it in 2015 with iOS 9.3.5. The AppStore requires support for current iOS releases, so developers naturally left these old versions behind. Nothing can be installed on it through the AppStore. It has an A5 core, 512MB RAM and 16GB of flash storage so it could still be useful as a light web browser, an ebook reader, a music player, or even idling away as a digital picture frame. Apple's walled garden of locked hardware, forced obsolescence, and single source for apps mean I have an otherwise usable device with which I can't do anything. I have Android tablets– a HP Touchpad developer edition and a Toshiba Thrive that was for my son when he was still in a car seat on trips– that are similarly obsolete but at least they have unlocked bootloaders and I can update them to a semi-current Android release (for a painfully slow experience, I don't recommend this).
There's a pandemic, in case you haven't heard, so going to the nearest Apple store an hour away for $20 in credit isn't an option even if I would consider owning an i-device. So now I'm looking down into the rabbit hole of jailbreaking and running VM's and Wine to try all kinds of questionable code from random file sharing sites and trying to game or sidestep Apple's code signing requirements. Awesome, I think I'm good without that. I'll put it in a drawer until I feel motivated to bring it to recycling, probably along with the old Android tablets.