I wrote up a screen plan for my kids. They get an hour of screentime a day (2 hrs on weekends). They have to write on the whiteboard the time they start, and I have a camera watching the whiteboard (with sound off) if I need to verify they put their devices back afterwards (I've never had to audit them yet).

It has worked wonders. It is not perfect but my two 8 and 10 year old daughters have used it. My 12 year old son, battles me in every way, but I feel like it is a small war instead of WWIII now.

They get a bonus of screen time before school if they get all their chores done. The whiteboard has all those chores. I hate them having screen time before school, but I like that I no longer am fighting with them to get their socks on.

This is a drastic improvement from a few months back.