How much land is enough? ISM has long recommended that schools acquire a minimum of 40 acres (and ideally 100+ acres). This is particularly true where the school is (or includes) an upper school with its enormous athletic needs. In all our work with schools, ISM has not encountered one that complained of owning too much land, but has found many that regret not acquiring land when they had the opportunity. Today, of course, land is so much more than athletic fields. Schools see the importance of outdoor classrooms, adventure playgrounds, organic gardens, ecological preserves, wetland conservation, and so on.