One of the most difficult challenges New Yorkers face is finding space — space to live, space to work, space to build — and finding space for a garden and an environmental learning center is no exception. Following the old mantra “if you can’t build out, then build up,” the Greenhouse Project at the Manhattan School for Children PS 333 made up for their lack of backyard space with an incredible rooftop destination for their staff and students. Designated as a meeting point focused on urban agriculture education, this rooftop glasshouse classroom features a hydroponic farm with an innovative system of teaching sustainability in the city.