My kids and I attended a presentation by Rory Neary and Pieter Veenstra of www.powerapps4kids.com where Pieter’s son Leo did a demo of his Planet PowerApp live on Zoom. Rory then went on to demo a 5-minute PowerApp that kids could build using sign language gifs available on their GitHub. The solution used a text input field that was then split across a Gallery using a dynamic reference to the animated gifs held on GitHub.
My son, Alasdair, and I then went on to build the same demo app and he learned how to build his first PowerApp solution.

Thank you PowerApps 4 Kids. The website has loads of resource to teach your children how to use PowerApps.