Katie McMorrow, 9, and Claire Miller, 8, scanned the snow-covered yard and, after a pause, took off to one of the nearby houses in the Great Hollow Nature Preserve.

Their mission was to find a good shelter for their “Jell-O Babies,” or cups of mixed gelatin, to keep them from freezing in the winter.

The friends, both of New Fairfield, found a sunny spot on a porch and set to work hiding their cups in piles of leaves.

“There’s a lot of sunlight and it’s away from predators,” Miller said. “We covered it up in leaves so it wouldn’t get cold.”

This was just one of many activities campers are completing this week as part of Great Hollow’s winter break program. It focuses on teaching children about the environment in a hands-on way outdoors and offers an educational day program for parents to send their children when school is not in session.

“We’re filling that need a bit in this area,” said Chad Seewagen, Great Hollow’s executive director.

Campers have spent this week in the classroom learning about various environmental topics, then practicing those principles outside, though not as long as initially planned, due to the colder temperatures. On Wednesday, campers imitated the flying “V” formation geese use when migrating, by walking in groups of four in hula hoops. They also used a parachute to mimic how mice travel below the snow and fox hunt them from above.

“It’s very fun,” Katie said. “You get to learn new stuff and go outside.”

She said it complements what she’s learning in school too.

Claire said the hands-on component helps her better understand the material.

The winter camp was first offered last year and participation tripled this year, with nine children enrolled at the peak this week. It is open to anyone, with most of the campers coming from New Fairfield, Danbury and Sherman, though the preserve also tends to have residents of New Milford and New York attend events.

Seewagen said its programs are continually growing as the organization itself grows. Great Hollow opened as a nonprofit preserve about a year-and-a-half ago, thanks to the donation of a Sherman philanthropist. It was previously a wilderness school for the YMCA and before that a research site for Wesleyan University.

Walter Merritt deeded his more than 1,600 acres to the university when he died in the 1960s with strict stipulations that the land can only be used for environmental education and research. In the 1980s, New York took the portion of the land in that state and gave it to Putnam County, leaving about 825 acres in the preserve, which straddles Sherman and New Fairfield.

“It’s never been open to the public before our organization was established,” Seewagen said, adding there are about seven miles of trails.

Great Hollow now focuses on offering educational programs for children, the community, as well as research on wildlife ecology. The preserve partners with several universities and the state Department of Energy and Environmental Protection on various projects and researchers can apply to stay on site for field work.

The preserve has started a homeschool program and hosts other community events on the weekends.

“We’re filling the voids here and there as they arise,” Seewagen said.

kkoerting@newstimes.com; 203-731-3345