Best Digital Demo Board for Teaching?

What is the best digital demo board software for teaching chess to a group of kids? A board where you can load your ready-made positions, draw arrows, and mark important squares with different colours, etc? (Preferably one which is stored locally, so I do not need to rely on the internet.)

I want to to use the Chessify App to create FEN files from printed diagrams, and then upload these to  the digital demo board. I connect my computer to a large screen and start teaching with all my diagrams just a click away. Wouldn't that be nice?

Any ideas? All suggestions welcome.

Thanks

Did you ever figure this out?  We are starting a chess program and using the ChessKid curriculum.  I am trying to figure out how to preload various board layouts also, without having to make multiple analysis boards on chess.com.