"Play is the work of childhood". Like most cliches, that's absolutely right. Children make dramatic entrances on the stage of life and then continue to rehearse their roles through the act of making believe until they're ready for their debuts in what we erroneously label "real life". For there will never again be any part of life more real than childhood.
At P.S. 161, located on the edge of a Latino neighborhood in West Harlem, I had the opportunity to run this metaphor to the ground when the teachers and parents decided that their playground would reflect the school's focus on "multi-culturalism and performing arts". In fact, the opening performance was already chosen before it was designed - "Romeo and Juliette in Spanish and English" and it turned out to inspire the design of "El Teatro Globo", a mini-Shakespearean playhouse where PLAY really is the thing.