The 4 children each have an element but they have to press a symbol hidden on the skin of the enemy to activate their powers. I remember them changing into a look that represents an animal (fire was either a lion or tiger, wind was a pink butterfly, thats all i remember).
This is Combo Niños.
Combo Niños is an English-language French animated television series created by SIP Animation in collaboration with Jetix Europe and TF1, aimed towards the 6–10 years old audience. The series is about the adventures of 4 juvenile capoeira practitioners with the mission to protect the city of Nova Nizza from attack by mystical creatures from another dimension called "Divinos".
The Combo Niños have the ability to transform into mystical beings in animal form by touching one of the totems that appear on the creatures. This form gives them unique skills that serve them in the battle against the Divinos and to perform special attacks called Big Blastico, used to return a Divino back to its own dimension.