With all the buzz around green building, it's no surprise that K-12 schools around the country are starting to see the benefit of sustainable design. In fact, there are 32 K-12 buildings in the US and Canada that have already been LEED-certified.

Incorporating environmentally elements such as energy-efficient lighting, heating, and cooling, locally-sourced materials, renewable energy sources, non-toxic sealants, adhesives, and paints, green roofs, and greywater systems, schools are creating buildings that are working models of sustainability, providing excellent tools for lessons along with the obvious benefits to the environment.

Not only is the environment benefitting, but green school design serves other purposes, as well. The Elk River Area School District, located in Minnesota, has three LEED-certified schools, with a fourth, Twin Lakes Elementary, set to open in for 2007-2008 school year. District officials estimate that their green buildings will save the district $300,000 annually in operating costs, mostly due to decreased energy costs. Classrooms are designed to maximize natural light, using high, slanted windows to let in as much sunshine as possible. Light sensors automatically turn off lights in rooms when enough natural light is present. Light tubes line the hallways, funneling sunlight into the common areas.

Pine Jog Elementary School, which broke ground on Wednesday and will be Florida's first LEED-certified school, will use strategically-positioned "light shelves" to bounce sunlight around classrooms. Pine Jog officials note that although building costs will be 5-10% higher than a conventionally-built school, the district estimates that they will recoup that cost within five years due to energy and water savings. Greensboro, North Carolina's North Guilford Middle School even has three constructed wetlands that naturally filter sewage through a series of plants, grasses, and algae, with the cleansed wastewater used for athletic field irrigation.

Elk River officials cite research claiming that students who study in naturally-lit clasrooms performed 25% better on math and language arts tests. Their district, a previous winner of the EPA's Excellence Award in Indoor Air Quality, installs diffusers in all classrooms, which circulate clean air into classrooms, reducing airborne illnesses, which any teacher can tell you run rampant at elementary schools.

The buildings and their construction are environmentally-friendly, but thoughtful, user-friendly features will help promote sustainable-living habits among students, parents, and staff. Pine Jog will have ample bicycle parking, and preferential staff parking for those who drive hybrids. Great Seneca Creek Elementary School in Maryland has dual flush toilets, complete with (ahem) yellow and brown labels for the appropriate flush in the kindergarten rooms. All schools incorporate outdoor learning spaces and learning labs centered around the building design, seamlessly integrating sustainabilty across disciplines as a tool for learning traditional concepts.