November isn't a bad time to visit Monaco and Nice. Warmer than much of France and nearby countries.
You can get the Foehn and the Mistral, and some rain but also some really nice weather.
Not mentioned in the attractions of Monaco above (unless I missed them), also consider the mechanical aspects of making a hilly principality easily usable for the mobility challenged in the population. Monaco has done a great job using public outside escalators and elevators, multi level crossings and all sorts. I love to find ways around and see just how many hills I can beat.
The train station for one, there is the entrance near track level at the top of S Devote (F1), an exit with a travelator down by the port near the F1 finish line, and an exit at the top of the car park above the station convenient to Jardin Exotique.
Speaking of which, the Jardin Exotique (and one at the top of Eze le Village) are great year round.
The rose garden won't be at its best in November but the Japanese Garden on top of a car park will be.
You can stand at the Café de Paris and the Casino without going in and look right down the hill to S Devote, and then swing around in the little park and see the road down to the hairpin.
There are all sorts of views of parts of the F1 track but your son will need to know what to look for. Remember that the track goes in the opposite direction of traffic in places. Careful in and around the tunnel, and traffic in Monaco does not watch out for F1 fans leaping out.
Princess Grace is buried in the chapel near the palace - a nice place to visit. The Prince's car collection (the deny it is a museum) is also right there.
There is the Changing of the Guard, and mentioned above I love the Aquarium.
People who don't go to Monaco with a prejudice that it is only a casino and lots of rich people actually find quite a lot of interest and plenty to do. Don't forget the harbours - large and little - and what's nearby, and a McDonalds with a great view of the petit harbour, and the beach, and and and....