I made this basic website for my daughter (6) to learn how to move chess pieces. I wanted a simple game which didn't have all the rules, just how to get from A to B with a piece. Admittedly, as soon as I made this a friend pointed out https://lichess.org/learn which is really nice!

There are a bunch of settings you can tweak to set the difficulty etc. Anyway, maybe will be a fun (short) diversion.