What is a common use for a sand pit?

A sand pit is primarily designed for children's play, providing a safe and engaging environment where kids can dig, build, and explore. This type of play encourages creativity and imagination as children construct various sand structures, learn about textures, and practice physical coordination.

While sand can be found in environments where sports are played or even used in construction, these contexts typically do not involve a designated sand pit specifically meant for play. Many recreational areas have sand pits specifically to cater to children's play needs, making it a common and appropriate use. The other options do not reflect the primary intent of a sand pit, thus supporting the choice of children's play as the most applicable answer.