Overnight Site Around Mont Saint-Michel

We're heading down to France and looking for an overnighter around 2 hours from Cherbourg; thinking Mont Saint-Michel. If it was just myself, I'd use an aire but with the wife and 3 kids I'd prefer to be booked in advance. No messing around, just pull up for the evening and let them stretch their legs after being on the ferry all day and then driving.

Some sort of playground would be great.

Seems to be a number of sites in that area so would appreciate any experienced recommendation and/or website links.

This seems ok - https://www.campingsaintmichel.com/en/ - anyone stayed there?

Yes I've stayed there 3 times they have a pool, bar, playground and small pet Farm. they are an ACSI site.
There is a little bar in the village on the right of the site, 5min walk, out trough the side gate they usually do a BBQ outside in an open fronted barn at the roadside you will probably see it on the way past if you come in on the D43.

We did Aux Pommiers first 2 nights off ferry end of May it has playground and swimming pool(an Aire along road from it, though not much cheaper than campsite, depends if you have to pay per child in campsite.
Driving back to Cherbourg to fill in time went along by Utah Beach there was Camping Utah beach, we weren’t in it.
Think ACSI too.
Our last campsite was Les Iles inland from Granville it was great, on each pitch there was a private toilet, shower, washbasin and sink on deck for washing dishes.
You won’t have much time on ACSI discount as now July. Notice there is a symbol of 2 children holding hands in ACSI book where children under 5 are free.
Try app Park4night. We didn’t use but lots of info.