It’s not often kindergarten students get to watch their teacher smear mud on her face — and leave the mud on until the day’s final school bell rings.

It’s even less often the students get to spatter their own faces with wet dirt and leave them filthy for an entire school day.

But such are the tricks of the teaching trade as practiced by Eden Prairie educator Jen Heyer, 42, whose regular forays into the “wilderness” surrounding Cedar Ridge Elementary School encourage her students to learn more than just reading, writing and ’rithmetic.

“I started thinking about trying different teaching methods quite a few years ago,” Heyer said. “I had been reading about an American who was teaching in Finland, and about how in that country, regularly scheduled ‘unstructured’ classroom time benefited students, so I thought I would try it.”

A graduate of Augsburg University in Minneapolis, Heyer also holds two master’s degrees. She’s as intrigued by the way kids learn as by what they learn.

A resident of the greater Twin Cities, along with her husband and their 7- and 10-year-old sons, Heyer also knows firsthand the importance the outdoors can play in kids’ lives.

Yet she’s aware many metro kids aren’t involved in outdoor activities, whether hunting, fishing or simply strolling in a park. Access is a problem for some. For others, it’s a lack of money. Other kids’ parents are too busy or simply disinterested.

Richard Louv’s game-changing 2005 book, “Last Child in the Woods,” in which he coined the term “nature-deficit disorder,” gave voice to the individual and cultural downsides of raising kids “outside of nature.”

Louv said kids should spend as much time as possible outdoors — for their own good, and everyone else’s.

“Nature-deficit disorder,” Louv wrote, “is a way to describe the psychological, physical and cognitive costs of human alienation from nature, particularly for children in their vulnerable developing years.”

An angler herself who grew up in an outdoors-oriented family, Heyer was prompted four years ago to integrate nature into her teaching by a few kids in her class “whose needs I just didn’t think I was meeting.”

“I needed to change things up and recalling the unstructured time practiced in Finnish classrooms, I told the kids, ‘OK, we’re going to start a running club,’ “ she said. “So every morning we’d go outside and run around the playground a couple of times. When we came back inside, I noticed an obvious difference among the kids. They were ready to learn.”

Kindergarten students are generally 5- and 6-year-olds who are expected to learn to read, write, do simple math, and understand the basics of science and health.

Kids who graduate from Heyer’s kindergarten class also will know how to get dirty.

“One of the first things I did when I started taking the kids outdoors more often was make them go barefoot,” she said. “I spent almost my whole childhood barefoot. But these kids didn’t want to get their feet dirty, or their hands dirty. They especially didn’t want to get their faces dirty.”

Which in part is why, four years ago, Heyer developed “Wilderness Wednesdays,” in which her class spends one day each week outside, learning everything they would otherwise learn indoors, but doing it in nature.

She initiates the kids to Wilderness Wednesdays by muddying her face and theirs. (See some of the adventures online at twitter.com/heyerlearning.)

“The first year I did it I had a boy who cried after we rubbed his face with mud, but I said, ‘We’re leaving it on all day,’ ” Heyer said. “The willingness to get dirty, to dig in the ground and touch trees, is all part of learning to be comfortable with nature, not apart from it.”

Heyer’s teaching methods are also practiced in European (and some American) “forest kindergartens,” whose advocates believe early childhood education should be play-based, child-led — and outdoors.

“On Wilderness Wednesdays, we complete the same lessons outside we would do inside,” Heyer said. “But the teaching method is different. Outdoors, I’m not the expert, all of us are. I might say, ‘Let’s build ramps and roll pumpkins down the ramps and see how far they’ll go. Now how will we do that?’ ”

Serendipitously, Heyer was introduced a couple of years ago to Twin Cities members of Safari Club International, who last summer awarded her a scholarship to attend the group’s American Wilderness Leadership School in Wyoming. There she met people from throughout the nation during an eight-day immersion in conservation methods and principles.

The experience strengthened Heyer’s belief in the importance of nurturing kids’ — and adults’ — connections to nature.

Even if that connection means cleaning storm drains, as Heyer’s students did Monday — Earth Day — as part of Hamline University’s “Adopt a Storm Drain” program.

“The kids pulled on rubber boots that were donated to us and waded in the water with rakes and shovels, and removed debris that otherwise would have ended up in creeks or rivers,” Heyer said.

Nature-deficit disorder is real, she believes. But hopefully not with her students.

“I send out surveys to the parents at the end of the year,” Heyer said, “and the most frequent response I get to Wilderness Wednesdays is that they wish they could continue in the higher grades.”