In 1999, Hollywood Elementary and 33 other Maryland schools were the first to receive the Maryland Association for Environmental and Outdoor Education's (MAEOE) Green School Award. This began what has become one of the best recognized and most imitated Green School programs in the nation. But what is a green school? It depends on who you ask. For the past decade, to be a "Green School" in Maryland meant to have received recognition from MAEOE for the integration of the environment throughout the curriculum and sound environmental practices within the school. Today there are many competing "Green School" programs and awards with most reflecting the current concern with energy conservation and environmentally-sound building design. The MAEOE award stands above all others in both its rigor and its emphasis on incorporating environmental education throughout a student's educational experience. The Maryland Association for Environmental and Outdoor Education describes the Green School program as, "a holistic, integrated approach to authentic learning that incorporates local environmental issue investigation and professional development with environmental best management practices and community stewardship."

As of May 2011, St. Mary's County can boast of 14 MAEOE Green Schools and one Green Center.