While environmental groups prepare to commemorate Earth Day next week, students in elementary schools across Mountain View are getting their hands dirty, and experiencing a little bit of Earth Day every day.

The Living Classroom is a program adopted by the Mountain View Whisman School District that gets students outside and exploring nature, particularly plants, right on campus. People in the program help build and maintain gardens at all the elementary school campuses in the school district, and volunteers help to teach as many as nine lessons to each class per year.

Last month, Living Classroom completed a native garden at Theuerkauf elementary that cuts between classroom buildings within the school grounds. It holds 32 different plant species, each one native to California. All the plants are labeled to show the plant's name, what it's known for, and whether the Native Americans had a use for it.

Choosing the native plants wasn't easy for Vicki Moore, Living Classroom's executive director. Moore said she had a list of criteria the plants had to meet to be included, such as whether they fare well in a garden environment. Sometimes parents suggest plants that they think would be a great addition to the garden, but would die outside their normal habitat.

Sometimes plants are included for aesthetic reasons, like the California fuchsia. While most California plants are in summer dormancy, the fuchsia blooms vibrant, tube-shaped flowers. Though the flowers put some much-needed color in the garden, Moore said they also have an important role in feeding hummingbirds during the summer.

Above the garden is a sign that explains what the native garden is, both in English and Spanish, and who funded it. Moore said most of the signs are in two languages because of the high population of Spanish speakers and English-language learners at the school.

Off to the side of the Theuerkauf campus, along the edge of Stevenson Park, is the Living Classroom edible garden. In front of the garden is a sign that tells visitors that they can enjoy looking at the plants, but to leave the fruits and vegetables for the students. Moore said it's been a pleasant surprise that the edible garden which is in a public area has not been tampered with or vandalized. "I think it's the sign," she said.

The garden holds a host of edible fruits and vegetables: peas, tomatoes, broccoli, carrots, and more depending on the season. Mallory Traughber, the program director for Living Classroom at the Mountain View Whisman School District, said each of the edible plants is associated with the curriculum for one of the grades. For example, second-grade kids will do a project called "from seed to pretzel," where they grow winter wheat, harvest it and grind it to make flour, and use the flour to bake pretzels. In third grade, children grow squash, beans and corn in unison to learn about inter-cropping, where plants grow together and rely on each other.

Five of the district's seven elementary schools have native gardens, but all seven have edible gardens. Moore said the edible gardens are important because they expose kids to the source of their food and give them the opportunity for hands-on learning, which is how kids learn best.

By the end of the school year, the Living Classroom program will have taught almost 300 lessons across 49 classrooms. Moore said the teacher participation rate, at 96 percent, has been overwhelming.

A majority of the lessons are taught by trained volunteers from the community, including parents, retired teachers and local college students.

Living Classroom is mostly funded by private foundations, corporations and the Mountain View Educational Foundation. This means the program does not cost much for the school district it just needs to provide a storage shed, some maintenance, and an office to work out of. What may prove to be a barrier, Moore said, is if the district can't get enough private grants to get the program up and running at all of its schools.

Moore said the Living Classroom program is refined each year to better match the curriculum for each grade level. The lessons are not designed as extra content the teachers have to worry about covering, but instead as an enhancement of what they had to teach that year anyway.

Although the native and edible gardens expose kids to the natural world and environmental science, Moore said, the Living Classroom program can't replace the experience of going out on field trips to the outdoors, and should not be seen as a substitute.