Along the Rhine, no.

You could do a trip down the Seine which gets pretty nice in places with castles etc along the way. Giverny gardens is down that way and that makes a fine day out.

You could look at other rivers, the Mosel is just about reachable, you might like Luxembourg city, or Rheims or even medieval Strasbourg.

Mont Saint Michel is sure to interest a 12 year old.

^^ So won't Provins, which is 1-1/2 hours by train from Paris and will only cost a maximum of 16.10€ for a train ticket (and possibly cheaper) and doesn't require booking train tickets 3 months in advance or a 4 hour journey each way.

Mont St Michel is really too far for a day trip. Well, you can do it but it's very far away.

Provins is a good idea and it's in zone 5 of the RATP Paris metro area, so you can just buy a one day Mobilis for 5 zones and it will cover your trip to and from and all your other transportation usage that day in Paris. It leaves from Gare de l'Est, I noticed it when I was doing the same thing to go to/from Meaux a couple months ago (also used a Mobilis which was very convenient as I need to take a bus a couple times in Meaux and the Mobilis was good for that, also). That one-day transportation pass is 16.1 which FMT is probably referring to but some people probably wouldn't think of it when talking about train tickets.

If only the OP would ever decide to come back to the thread I suppose all our advice would be meaningful but sadly, like some other posters, we will likely never hear from travellingcouple again so I'll refrain from posting further on this thread unless they have the courtesy to return and thank those who have been polite enough to respond.

I gripe about this all the time..so I agree, FMT

I did come back to answer a question asked on when we were going .I was away yesterday and have been researching some of the towns just now.
I do appreciate all information and suggestions and hope they keep coming but Only starting this thread 2 days ago I think you French mystiqueTours should give some of us more than a day to reply and express our appreciation.
Any recommendations on museum passes anyone.
Thank you in advance.

Well my apologies travellingcouple but it gets frustrating when people abandon threads or provide little in the way of feedback after advice has been offered so I'm glad you returned.