Normandy/Paris itinerary check

And the clock starts on how soon someone will scold you for driving on the same day as you land.

I'd say that's an ambitious itinerary, but that is personal preference (I prefer to take more down time to sit in a park or have a coffee and soak it all in). There's nothing not doable in your itinerary.

No, there's nothing that's not doable, but I do have a couple of thoughts.

First of all, on your arrival day - you might want to rethink your lunch plans. You don't land until after noon. It will take more than an hour to clear the airport and pick up your car, and then at least 2+ hours drive to Rouen. ( I'm biting my tongue about the wisdom of such a prolonged drive after a transatlantic flight). That has you arriving there no earlier than 3:30. Probably 4:00. And you still have another 1.5-2 hours to Bayeux. As an alternative, I'd suggest taking a taxi into Paris, then a train to Caen, and renting the car there.

MSM on day 2. Arriving in the early afternoon (is this in summer?) will put you smack in the middle of the heaviest crowds. And when I say crowds, I mean shoulder to shoulder and chests to backs. But certainly doable.

The trip is very aggressively stacked, but if you can be somewhat flexible and willing to forgo some sights when (not if) someone hits the proverbial wall, then it can work. Certainly no one will complain of boredom.

Ricky,
Whew! Well, your plans could work if everything (and I mean every step) goes at maximum efficiency. Landing at 12:35 and getting to Rouen within 3 or 3 1/2 hours assumes you are one of the first to deplane, have short lines at immigration, car rental and pick up takes less than 15 minutes (unlikely), and finding your way out of CDG and onto the autoroute to Rouen immediately. We have picked up rental cars at CDG more than once, and it usually takes about an hour from walking to the car rental office to driving out of the airport (longer if there are lines at the office...not uncommon). Parking in Rouen isn't usually easy, but you could be lucky in finding a spot at a public lot. I would guess your arrival time at Rouen to be closer to 5:00. Your lunch here would really be an early dinner.
The drive to Bayeux from Rouen takes 2 hours. (I know, websites say 1 3/4 hours, but that is optimum.) You may have hit a wall by then.
Day 2, going to MSM in the afternoon gets you there with the big crowds. (Figure 1 1/2 hours driving, another 1/2 hour to park and make your way to the Mont. Reverse on the way back to Bayeux.) Maybe you could spend the first night at Pontorson or a place close to the Mont? See it in the morning, then drive to Bayeux in the afternoon. You might get there in time to see the tapestry or cathedral in there late afternoon. Then your tour on day 3. These first days seem difficult to me.
On day 4, if you want to see the Pegasus bridge (near Caen?), you could see it and drop the car in Caen and take the train to Vernon (for Giverny). There are 18 trains most days, taking 2-4 hours depending on which one. The trains from Vernon to Paris are also frequent. I would avoid driving in Paris if at all possible. It is worse than Boston! Of course, you will have your bags, and I don't know about bag storage in Vernon. If you decide to drive there, drop your car before going into Paris if possible. And give yourself at least 2 hours at Giverny. There is a nice little cafe on site for lunch.
Day 5 and 6 sound good, but fyi, Napoleon's Tomb at the Invalides (army museum) is a short walk from the Eiffel Tower. And the museum has lots of cool stuff to see and interest a 13 year old. (Suits of armor and medieval weapons!) I would do this on that day. You could still metro or walk to the Arc de Triomph. (Personally, the Champs Elysees is disappointing, but you may enjoy it.) This frees up time on day 6 for more time at the Orsay museum. You don't want to rush through that.
Day 8 is good except you might find you need to drop Palais Royale or Orangerie. The Louvre to Tuileries to Orangerie are a natural progression. Maybe lunch in the Tuileries near the Orangerie before going in. There are some food options around there.
Day 9 sounds okay also.
Your days are pretty packed, but doable. Just rethink your first 4 days, perhaps. Remember that drive times are always a bit lionger than Google or Viamichelin, etc. state. They don't figure in gas/food/comfort stops, and usually assume you are on the fastest roads (autoroutes). We always add about an hour to their projections. If we are wrong, all the better. If they are wrong, we feel pressured.

What month are you going? Summer means more people, so longer lines. Be sure to reserve your tickets to the Louvre, the Musee d'Orsay, the Orangerie, Ste. Chapelle, the Eiffel Tower (if going up), the DDay tour, the Giverny gardens, Notre Dame, Versailles. You can get a Vedettes de Pont Neuf boat ride on the Seine the same day usually. They leave often.

Best of luck in your travels. Have fun!

Thanks for the feedback.

I’ll bump Rouen into the highly unlikely bucket.

For MSM I’m hoping the crowds in June start to thin out by late afternoon, 3:00 or so, but I’m bracing for a throng of humanity everywhere I go this time of year.

I like the idea of swapping out Champs-Élysées for Napoleon's Tomb at the Invalides to free up some time on day 6.

As long as we hit our top one or two items each day we are content. The rest is a nice to have.

Thanks again