Never underestimate the initiative of a few teenagers, especially when it comes to greening their school. Yarmouth High School in Yarmouth, Maine, is now solar-powered, thanks to a few motivated seniors. The students, with help from local renewable energy company Revision Energy, secured a state grant to cover 80% of the $33,000 project. They made up the difference with profits from sales of T-shirts and dance tickets, as well as a donation from a local organic restaurant. Greening your school -- or your child's school -- doesn't have to mean going off the grid. There are plenty of smaller projects that parents, children and school administrators can tackle to make their school a more environmentally friendly place. Even better: According to a 2007 report by building firm Capital E, students and workers in green buildings are healthier and more productive. In addition, the report found that, on average, the cost of converting a school so that it meets LEED (or state-equivalent) qualifications was $3 per square foot, but the financial savings of a green school was $74 per square foot. The end result: a net savings of $71 per square foot annually. Here's how to green your school: Reduce fuel use and pollution by making school grounds a "no idling zone." Clean School Bus USA's National Idle-Reduction Campaign suggests that buses limit idling time during early morning warm-up to the three to five minutes recommended by the manufacturer. In addition, buses should be turned off when waiting for students. Consider switching the bus fleet to a cleaner-burning fuel like natural gas if the school system has the money.