EVERETT — Fifth-grader Sommai Phanhsiry used her foot to push a shovel as far into the ground as she could.

She and others in her class at Horizon Elementary School on Wednesday worked to clear a school wetland restoration site.

“We’re learning to take out all of the invasive plants and to help the other trees and plants grow,” said Sommai, 10.

The activity was part of an all-school celebration for Earth Day, which is to be held later this month. Throughout the day, third-, fourth- and fifth-grade classes went outside to help with on-site restoration work and participate in a lesson about trees given by members of EarthCorps, a nonprofit formed to work on environmental projects throughout the world.

In addition to clearing invasive plants, students filled buckets with mulch and passed them off to classmates who poured it around a newly replanted area. During the lesson time, students learned about the different trees in the wetland and about how people used trees in the past.

“Trees helped Indians a long time ago,” said Jabez Nunez, 9. “They helped them build baskets, make medicine and do a lot of things.”

Third-grader Omara Santiago, 9, said she learned about evergreen and deciduous trees.

“We learned about all the different trees,” she said. “We learned we have to take care of the trees.”

A presentation about trees was given to kindergartners, first- and second-graders by representatives from the National Forest Foundation and U.S. Forest Service.

Students touched fur animal pelts and looked at salmon eggs during the presentation. First-grader Veronica Mishchenya peered at the eggs and samples of young salmon kept in clear containers.

“They’re so cool,” she said.

Veronica, 7, said she likes to climb trees and knows how to take care of a young tree planted at her home.

“I give him time, air and sun,” she said.

The Horizon wetland area includes a stream and a peat bog and is roughly a third of the school campus, said Principal Leslie Clauson. She became interested in clearing the area of invasive plants in 2010 and contacted EarthCorps for help.

“Originally it was to create more stewardship and teach that the wetland is an important environmental land that we need to take care of,” she said. “It’s my hope that teachers will use it on a monthly basis as a field trip and tie it into what kids are learning in science.”

A party of volunteers including Boeing employees, Girl Scouts and Boy Scouts also gathered at the school on Saturday to work at the site, Clauson said. The school hosts events twice a year where students are scheduled to do mulching and planting.

Third-grade teacher Stephanie Kirkpatrick said her students enjoy being on the wetland site.

“A lot of these kids have never been to a forest,” she said. “They love it.”

Amy Daybert: 425-339-3491; adaybert@heraldnet.com.