Adventurous visit to southern France suggestions

Maybe the red-rock village of Roussillon? I haven't been there myself (hard to reach without a car), but others have praised it here, and I know there's a path around the weathered rocks--something for the kids to do.

I didn't go to the salt pans, but you can walk on top of the wall in Aigues-Mortes. There are flamingoes nearby; don't know whether they're seasonal visitors. You should expect to be among many tourists in Aigues-Mortes, but as always, there were blocks within the walls where I was alone.

Folks warn of a substantial mosquito problem in the Camargue. I didn't have any problem in the town of Aigues-Mortes, but for some reason I'm not very attractive to mosquitos, so I don't know whether they're just a problem out in the countryside or I was lucky.

The 'bullfighting' follows a circuit in local small towns around Arles and there are demonstration matches, kind of the equivalent of AA ball or spring training, where you could see rookies learning the ropes -- I bet your kids would get a kick out of that.

Another idea -- when water levels allow, there is kayaking/canoeing under the Pont du Gard.

Note also that Marseilles spawns some of the best club/dance music in the entire Mediterranean - it is literally too cool for school.

Are the salt pans in Aigues Mortes really that pink?

The marshes and evaporation basins around Aigues Mortes and le Grau du Roi contain a type of small shrimp which are indeed pink. The Flamingos heavy diet of these shrimp is what gives them their pink color. I believe the flamingos are there year round.

There are also enormous amounts of mosquitoes in the Camargue. It has fresh water marshes, some used for rice production, which breeds billions of mosquitoes.

How can I find out when they are "bullfighting" in Arles and is it easy to book tickets?

Traditional bullfighting season starts in September when most tourists have left. However, there is the Camargue version, course camarguaise, of bullfighting, which consists of raseteurs (young men trained to do this), grabbing little tags which have been placed at the base of the bull's horns. The raseteur with the most tags wins prizes and possibly cash. Most of the towns in the coastal area between Arles and Montpellier have these events during the spring/summer season. These events are more dangerous to the raseteurs than to the bulls, but even kids find them fun to watch.

Also part of the course camarguaise is Toro-piscine, an event where volunteers from the audience, (complete idiots in my view) stand motionless around a small swimming pool of water (piscine), at least for as long as they can, as a bull runs freely around them. The only way to escape the bull, if he charges, is to jump into the pool. The bull sometimes follows. It´s great fun to watch, I have no personal knowledge of how much fun it is to jump into a pool of water while being chased by a bull.

All of this is west of Marseille, an area the OP has not necessarily indicated as being part of the itinerary. Another very important factor for visiting the Mediterranean cost in the summer is for what month is this planned?

You'll find Marseille increasingly popular. It is a very, very trendy destinations these days, and in a good way.

I happen to have been to the Colorado Aventures zipline course: GREAT courses but they did not provide gloves, and my partner badly burned his hands on the wires. So, take some (cheap fleece gloves will do). Nearby Roussillon is probably the most interesting village for kids/teens.

Another vote for Roussillon. Les Ochres is unlike anything they’ll see at home and the museum there is informative without being too stuffy. The town itself is pleasant—something there for everyone. Nimes is wonderful for its very well-preserved arena. If they haven’t been to the Coliseum, I think they’d enjoy it. If you’re in Arles for the Van Gogh pilgrimage, there’s one there, but it’s not as impressive as Nimes. Point du Gard is a wonderful example of Roman engineering and is intact. You can walk across it, too. The museum talks about its construction and how the water was used downstream. I wouldn’t call it interactive, but it holds your attention. BTW, if you cook, pick up some sea salt from the Carmague. It’s nice for a little crunchy garnish on salads and the like.

Sounds like an amazing trip that your children will love.

I am in the beginning phases of planning for Provence, but from what I have read about so far, think they might like Isle sur la Sorgue and Fontaine de Vaucluse in the Luberon. My husband and I are thinking about visiting Isle for the huge market, then renting bikes there and cycling to Fontaine where we can canoe down the river back to Isle. The place that organises the canoe trips is : https://www.canoevert-vaucluse.fr/. While you are in St. Remy, checking out the roman ruins at Glanum might be fun for them.

A fun way to see the Camargue might be on a jeep safari.

Have you thought about going to Gorges du Verdun while in Nice? I so wish we had time for white water rafting or kayaking there.
A boat trip to Chateau D'If in Marseilles could be fun as well.

Don’t forget Monte Carlo is very close to Nice. Take your passports if you want to visit the famed casino. The journey from Nice to Monte Carlo is beautiful and stop along the way to admire the ocean.
Your kids will never forget seeing the famed sites and Ferraris.
If you do go to Arles (it is a beautiful town, filled with great history and a great arena) there are additional sites with VanGogh references.

Flamingos are there year around. I’ve seen them in January.
I was going to suggest the bloodless course camarguaise, too. Les courses and competition were being held last year with the Pass sanitaire.

Chico from the Gipsy Kings and his family have a dinner theater.
https://m.facebook.com/laguinguettedupatio/

Saintes Maries de la Mer in the Camargue is the site of a huge Gypsy (Gitan, Roma, Tzigane, Manouche) pilgrimage on May 24, 25. (And before correcting me, Gypsy is used in academia/ professional settings, and not pejorative.)

Another vote for Aigues-Mortes, Roussillon, Marseille but be sure to go to the abbey of St. Victor,. Particularly the crypt. And you can walk up the hills to St. Victor and Notre Dame de la Gard for a good workout.

Cassis, you can walk the trail into the Calanques, swim, have a picnic if fire alert is low. And, hike up Cap Canaille—magnificent, stunning, geographically much older that all the surrounding limestone.

Check out Fontaine-de-Vaucluse, France - there is a great walk up the river and I believe you can kayak there as well.

Thank you for all the suggestions. The Course Camarguaise and Rousillon both sound like adventures the kids would like. And I'm glad for the notice to bring gloves for the ropes course--we've done a couple of simple courses in the states but I never thought about gloves. I'm really starting to get excited--we leave in a little over 3 months.