The essence of the game is free playThat is, being able to decide who you want to play with, what you want to play, and when you want to play. And for this to be possible, it is necessary for adults to value play—which is not only a vital activity for children, but also a right recognized by the Convention on the Rights of the Child—and to provide the necessary conditions: time, adequate space, playmates, and autonomy to do so. Play is a source of physical and mental well-being, of learning, and has a positive impact on children's development. But the point is to play for play's sake. Play is a pleasurable activity in which the process is more important than the results. Productive lives, consumer activities, and other tasks and responsibilities that we adults have seem to extend into childhood, and we are gradually forgetting that children up to the age of 17 are still children and have the right to play. In fact, for 10- and 11-year-olds in Barcelona, ​​​​one of the areas of their lives that has been rated the lowest since 2017 is the amount of free time: half of them think they don't have enough.

When Clara Pons-Mesman's son was 2 years old, she realized that a process of transformation of the parks in the city where they lived was beginning: "They put rubber in most of the parks. I realized that the ground didn't allow him to play with the sand or observe the ants; he no longer enjoyed experimenting because he wasn't enjoying experimentation because he couldn't find it in the parks," Pons-Mesman explains of her son. From then on, she learned about it and realized that there were few references to promoting play in nature. This is the starting point of her project. Earth in the hands, which encourages free, outdoor play.