Here are a few websites for online note naming practice. I’ve been sending out print resources, but in case you don’t have a printer, the online games are engaging and can be used for your kids’ gizmo time…
https://www.musictheory.net/exercises/note
https://www.classicsforkids.com/games/note_names.php
https://www.notationtraining.com/
MusicTheory.Net has a wealth of resources for more advanced students as as well as the following link: https://www.musictheory.net/exercises
I hope this is helpful! I really encourage families to use the extra home-bound time for serious academic & creative progress in music.
Kindest regards for health & hope,
Rosanna