WASHINGTON — Schools featuring clean air, plenty of natural light, wastewater recycling, renewable power and other ways to lessen their impact on the environment also offer health and educational benefits for students and faculty, said a leading congressional advocate of that style of school construction.

Rep. Darlene Hooley, D-Ore., a co-founder of the Congressional Green Schools Caucus, said studies have found that students attending so-called "green schools" are healthier, with fewer incidents of asthma, colds and flu, and have improved academic performance, up to 18 percent higher. At the same time, building of green schools across the U.S. is expected to save $30 billion in energy costs over 10 years and cut carbon dioxide emissions into the atmosphere by 33.2 million tons.

Hooley said the green schools movement is growing and the number of them — now about 630 in 47 states, the District of Columbia and Puerto Rico — is expected to surge by 2010 and make up more than a quarter of all the green buildings in the nation.

In an interview, Hooley said she and other caucus members are trying to find ways for the federal government to aid local districts in the schools' design and construction.

Q: What are green schools?

A: They are energy efficient schools but more ... a series of things that really deal with conservation and recycling and the air inside the schools. To do that, you build the schools a little differently, such as maybe putting solar panels on the top of a school and using ... carpet (that doesn't release toxic fumes).

Q: Why is the number of green schools growing?

A: There are two reasons. One is the people are being much more involved in their impact on the environment and the other is knowing that if you have floors and rugs that emit gases that are not healthy for your students or mold in your classrooms, all of those are unhealthy for the students. They contribute to days of absenteeism.

It is being aware that there is a different way to build a school and of the fact that in the long run, it saves you money.

Q: Are green schools more costly?

A: They can be initially, but over a period of time they end up saving you money.

All the studies and statistics show that in fact, you save money with green schools — an average of $100,000 a year (per school).

Q: What is the evidence of green school benefits?

A: There have been some studies done, but more need to be done.

There are some things that we know.

Asthma, for example, is one of the largest reasons for students missing school.

If you build a cleaner school that has less gases in the air from the materials or is more resistant to mold, you will increase the number of days students spend in school.

Q: What can the federal government do to promote green schools?

A: We can provide incentives for schools that want to go green, either through help with the technology so that the school doesn't have to go out and hire an expert ... (or) if it costs more money to build the school than the conventional way, some other incentives.

We don't replace schools that rapidly but when they (local school districts) build a new school, we want them to use the newest technology available.

Reach Dennis Camire at dcamire@gns.gannett.com.