Last year, kids at South Fayette Intermediate School here in Pennsylvania were given a maker problem as old as the agricultural revolution itself: growing lettuce. Third-graders were tasked with building hydroponic gardens out of household items. All year, as part of the Grow-It to Go project for K−4 students, kids got their hands messy and examined how hydroponically grown plants compare with the ones they tended to in their raised-bed gardens outside.

When we think of the most cutting-edge examples of STEM education and making, lasers, 3-D printing, and programmable robots most quickly come to mind. But as eye-catching as tech is, educators with school gardens are teaching kids how a single turnip has systems just as amazing and complex. When school and community gardens are matched with STEM learning, it’s just one more way for kids to see, feel, and smell how STEM takes root in the real world. And earthworms and onions not only provide an unmatched chance for science learning, they’re also a springboard for talking about healthy eating and rethinking where our food comes from.

National nonprofit REAL School Gardens has partnered with 98 schools to build “learning gardens” for children in low-income schools with the aim of boosting STEM achievement. Teacher Scott Smith at Holiday Heights Elementary School in Texas recently talked with Edutopia about bringing his class out to the garden to tackle hands-on math problems like how many cubic yards of soil it takes to fill one of the raised garden beds.

And, of course, the garden lends itself perfectly to science lessons. Perhaps not coincidentally, REAL School Gardens has seen the biggest boost in science test scores in its partner schools.

Smith said the benefit of seeing textbook diagrams come to life makes science real for kids—like when he asked his students to put plastic bags over the plants and measure the condensation later. “Until they see that magic happen, ‘transpiration’ is just another big word with -ation on the end of it,” he said.

Here in Pittsburgh, school and community gardens are as active as all the other hands-on programming sprouting up throughout the city. The ongoing Cook, Grow, Garden program at the Children’s Museum hosts workshops on everything from how to harvest healing herbs to building terrariums. Meanwhile, Tripoli Street Garden Nights give kids the chance to get dirt under their fingernails while gardening at the museum’s quarter-acre lot, Food City.

Last May, the Mattress Factory sponsored a program called the Germination Corps led by artist Jessica Frelinghuysen. Students toted around little “plant packs” filled with vegetable seedlings for a week while learning about food sustainability. The program culminated in a Plant Parade from the Mattress Factory to the YMCA Garden where students returned their plants to the community garden.

“I think in an era of GMOs and big box stores that remove our food supply so much from us; we need to think of ways to remake that connection with life, with where food comes from—with growing,” Frelinghuysen said.

Part of a national network, Edible Schoolyard Pittsburgh has been building and educating in gardens for nine years and now has five flagship schools that integrate garden activities into curriculum. Recently, local chefs demonstrated cooking delicious meals with the food the students worked so hard to tend to and harvest.

It’s not just schools diving into the benefits of homegrown plants. Julie Butcher Pezzino, executive director of Grow Pittsburgh, told NEXT Pittsburgh a new level of cooperation in city hall has enabled an uptick in more urban agriculture. Across the region, there are more than 70 community gardens, and Pezzino recently said there can be years-long waitlists for a single plot.

“Clearly,” Pezzino said, “people need to grow their own food.”

Getting kids (and adults) interested in healthy food and where it comes from has become a national effort and a key part in addressing the state of childhood obesity in the United States, where more than one-third of children and adolescents are overweight or obese. Just last week, students from schools with gardens joined Michelle Obama in harvesting squash, lettuce, and sweet potatoes in the White House Kitchen Garden.

But the chance for kids to dig around in a garden means more than enjoying carrots, learning about weather systems, or even the maker-like problem solving that comes with managing hungry rabbits or too much rain. As kids and educators poking around with trowels already know, it’s a place where STEM-related explorations grow naturally, season after season.