If we really want to power-up nature-based play, it needs to be available where children can enjoy it almost any day, without adult involvement or confining schedules. For most kids this means either home yards or neighborhood parks — and (sadly) only the former is likely to alleviate the fears of 21st-century American parents. Can a typical quarter-acre suburban yard actually support nature play? Or a city lot half that size? Or an apartment courtyard? The answer is yes, especially for kids of about two to eight years old. Younger children’s worlds are much smaller than those of adults. They don’t need sprawling spaces or eye-popping vistas. Their attention naturally focuses on tiny and manipulable pleasures: on dandelions rather than rose gardens; on earthworms rather than herds of bison; on a patch of dirt to dig in rather than a yawning cave to explore.