well, it appears that they key is to set up their google accounts under your own. Wife had set them up with basically "adult" standalone accounts.

Got them all set up with new accounts, did a factory refresh on the laptops, and we appear to be cooking along.

One thing I like is the screen time limits. They have ipads now but the iPads are too old to work with the IOS12 parental controls. I have Eero for my wifi mesh and it allows control over devices by time of use (say from 3pm to 7pm, or whatever) but not by total hours used. The total is way more important to me as they are still small enough that there's not much chance they're going to use the devices at an unapproved time.