Just as an FYI, my 9 year old filled up my 32gb pretty quickly. The newer apps require quite a bit of memory, and they don't really come with 32gb, part of that is already filled up with the operating system, so it isn't a true 16gb or 32gb.
When we bought my 13 year old an ipad mini this year, we opted for the 64gb. He hasn't filled it, but he has right about 32gb filled and we plan to download several movies for our upcoming trip.
Dawn