Sorry Marie, they are too young for Go Cart. There is one in Playa Flamenca but I think you have to be at least 8.
There is a good playground at the La Zenia beach (strait down from Villa Martin) and on some other beaches. There is also an amusement ground near Guadamar but I do not know exactly where, but close to N332.
There is also a water playground east of N332 opposite Carrefour on Av Delfina Viudes. Restaurant El Rancho near Los Montesinos have a pool if you want to have a lunch while watching your toddles.
In addition, we have two great pools in La Canada!
Great that you take care of the small toddlers so they don’t grow up to big toddlers.