Ipod and Classdojo

I recently ''restarted'' my ipod from scratch with a new apple ID. I had classdojo on the old account and downloaded and everything. However now that I ''restarted'' the Ipod with a new ID it wont let me download classdojo as it requires IOS 16. However apparently Ipod's do not have the option to update to that IOS.

Anyone know a way around this? We use the Ipod's and classdojo for our daycare educators.