As seen in USA Today. 

Waterless urinals. Geothermal cooling systems. Photovoltaic solar panels.

The space shuttle? Try your child's school.

Classrooms are slowly going green, prodded by rising energy bills, public health concerns and a general desire to adopt eco-friendly principles. Green schools cost a little more to build — generally 1% to 2% extra — than conventional schools but promise payback through lower utility bills and, some studies suggest, better student achievement.

"A school district that might have been thinking 'I can't afford to build a green school' is now saying 'I can't afford not to'," said Rachel Gutter, schools sector manager for the U.S. Green Building Council which certifies school construction projects based on environmental criteria.

Several states, including Hawaii, Florida and New Jersey, now require that new school buildings be more energy efficient, reduce their water usage and recycle more. In June, the U.S. House of Representatives sent a bill to the Senate requiring schools built with federal money to incorporate green elements.

Nearly 100 public and private schools nationwide have been certified by the U.S. Green Building Council since 2000 and another 800 are seeking certification.

Ohio has been a leader in the green school movement, Gutter said. Using money received through a legal settlement with tobacco companies, they are planning to build 250 green schools over the next two years. The state expects to save $1.4 billion in energy costs over the next 40 years thanks to the program.

It goes beyond simply imbuing a sense of environmental responsibility, green advocates say. Some of the elements can help improve schooling.

Studies in 1999 and 2003 by the Heschong Mahone Group, a California consulting firm that promotes energy-efficient design, found that children generally fared better on math and reading tests in schools where natural light was more prevalent because it improved student focus and achievement. "Daylighting," as it's called, is encouraged because it cuts down on energy bills by reducing the need for artificial lighting.

"Most of the time we don't even turn on the lights in my classroom because there's so much light from the windows," said Lily Kamali, 11, a fifth-grader who attends Great Seneca Creek Elementary School in Germantown, Md. The school was the first in Maryland certified by the green council.

With large windows a prominent feature in most classrooms, daylighting is a central feature at Fossil Ridge High School, which opened four years ago in Fort Collins, Colo. That's not just because it's one of several green elements, such as low-flow faucets and wind power usage, aimed at saving money.

School officials say it also helps student performance. Fossil Ridge Principal Dierdre Cook said there is no hard data to suggest daylighting is a reason the school, which draws from upper-income neighborhoods, scores among the best in Colorado. Still, she added, the airy layout of the campus and its emphasis on clean air contributes to an academically enriching experience.

"It's just a happy building. It gives you a sense of well-being," she said. "The better you feel about where you are, the better you're going to perform."

Not everyone is enamored with the idea of going green.

Federal lawmakers who opposed a green provision in a school funding bill that passed the House in June don't like what they view as Congress meddling in a local issue.

"The problem with America's public education system isn't that it's failed to build a sufficient number of green schools," said Rep. Roy Blunt, R-Mo., the GOP's second-in-command among House members. "The problem is it's failed to empower our communities, parents and teachers with the tools and authority they need to provide the quality educational experience our children need, expect and deserve."

Much of the focus has been on construction. But teachers, parents and children at those schools say it's easier to imbue pupils with a sense of environmental responsibility in buildings that promote those principles.

At Summerfield Elementary, a Neptune, N.J., school recognized for its green design, students go on nature walks, plant flowers and engage in recycling projects.

"I do find that whatever they learn at school comes home with them," said Loretta Eichenour, Summerfield PTO president and mother of two girls who attend the school. "They're more environmentally conscious and that makes everyone more environmentally conscious."

That's the way many students feel at Sidwell Friends School in Washington, where a renovated middle school includes photovoltaic solar panels on the roof to save energy, a wetland to enable the reuse of wastewater for the school's toilets, and plenty of recycled building materials.

"It makes you look at everything in a new way," said Chitti Raju, 14, an eighth-grader at Sidwell. "You're used to seeing all these renewable and sustainable materials (at school) and you go to your house and you don't see any of this and you're like, 'Hey Mom, we can put in different light bulbs that do this.' It really makes you think about these things."