I'm traveling with kids however would like to know what we can do such as snorkel, swimming with dolphins, cave exploration, etc. Open from a budget perspective if it will be an amazing experience, not touristie :)
For swimming with dolphins I have done the once in dolphindiscovery, they are great, especially Isla Mujeres or in Puerto Aventuras and there is also another one called delphinus that also well known but I haven't done it with them, however I have heard from friends good experiences. For snorkel I truthly recommend Akumal although is a little far from cancun but there you can experience in the ocean with turtles and nice views. Xcaret, is a great place for children even though is very touristic but i love going there. Try going to Cenotes Sac Actún, natural and beautiful places where kids can have fun. there are a lot in Riviera Maya were it is not necessary to go with a tour. for cenotes im sure you will find a lot of tours and most of them with great places, although i think a tour to this will be kind of expensive for the real adventurer of going by yourself maybe by car.
Try to see this once, these are other options for parks.
hope it helps
-riosecreto, aquarium, barco pirata
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I went and did the Xcaret expeditions. There are a lot to choose from. They will even get you from your hotel so no need to worry about transportation and the fee also includes food inside the park itself. I think it's a great experience not only for kids but also for adults! Have fun!