Fallen leaves crunch beneath the steps of 20-plus sixth graders as they run about with clipboards in hand behind Edgewood Primary School. Carroll Ritter watches the miniature scientists, equipped with tape measurers and calculators, in their quests to determine the diameters and circumferences of surrounding trees.

"Yes, I knew it!" exclaims a boy, pumping a reddened fist into the air when his math comes out correctly. Within the next 30 minutes, each student's calculations will prove a familiar mathematical concept: pi = 3.14.

"Today's exercise is a practical use of math with hands-on outdoor experience," says Ritter, the environmental education coordinator at Sycamore Land Trust (SLT). "A lot of subjects can be taught using the outdoors. It's fun, it's practical, and it's real world."

The Edgewood students are but a fraction of the children in Monroe County whose classroom curricula entail studies with the environment. Recently, heightened emphasis on the environment has become a trend, with teachers at both public and alternative schools working it into their lesson plans.

"Students ... come to school knowing we need to take care of the environment and with a desire to learn about how to do so," says Valarie Akerson, associate professor of science education at IU. "... Many teachers have begun to emphasize environmental education as part of their social studies as well as science lessons."

The environment, the teacher

Transitioning from the path to an open field a few hundred feet away, Ritter's students again pick up their tape measures. This time, he challenges them to estimate trees' heights, using trigonometry.

"The natural world is the perfect classroom for any subject," says Ritter. "You can write poetry, compose music, learn the sciences. ... We're trying to get kids outside the confinement of the four walls of a building."

Emily Sprowls, a science teacher at Harmony School in Bloomington, finds the environment a valuable tool in dissecting complex topics for her high school students.

"I chose to teach physics through the lens of renewable energy because physics ... is kind of hard to grasp," says Sprowls. "This is a good, hands-on way of looking at how these physical concepts apply to, 'How are you turning on the light switch?' and 'Where is our hot water coming from?'"

Ritter says it is a child's curiosity that makes the environment a great classroom.

"At an early age, kids still have that inquisitive desire to learn things," he says. "They find the outdoors a stimulating environment. It opens up a whole new world for the kids to do something real."

The environment, the subject

Sprowls's self-created game of "Rock Bingo" has 11 students circled around two wooden tables, searching their notes for answers to clues. All hope to get "3-across" and win one of the prizes she keeps stashed in her lower desk drawer.

Basic science courses are not all that Sprowls teaches. She also focuses on developing students' knowledge about the environment.

"[The environment] is something that I care a lot about," she says. "And a lot of our students here are thinking about that."

Sprowls focuses on the idea of the environment as a subject through renewable energy and environmental studies courses, among others, with students learning through field trips and guest speakers.

"One of my main ways of [teaching] is getting kids out to see stuff, and with renewable energy that's really easy to do," she says. "We visited ... a green-design building, we did an energy audit of a property Harmony owns -- a lot of 'out in the community' stuff."

Her focus on the environment is consistent with what Akerson sees for the future of science education.

"I have definitely seen an increase in education students interested in environmental education," Akerson says. "We have been partnering with Sycamore Land Trust, which has led some outdoor education lessons for all our elementary science methods students this semester."

This trend bodes well for Ritter's goals at SLT.

"These children are going to be the stewards of the properties that ... will remain in southern Indiana," he says. "We are trying to instill good environmental ethics in the kids that are here."

Mary McConnell can be reached at .