Junior Michael Starliper, 17, said last year's resource management class prepared him for projects like this.
"We learned how to plant just about anything," Starliper said. "I hope people look and say, `There are good kids in Clear Spring, always helping the community.'"
"And I hope they respect the trees," said senior Jason Reed, 18.
Students installed about 40 trees, including Eastern hemlock, Red maple, Pin oak and American beech.
"Arboretums are places you go to identify plants - living museums," said Washington County Forestry Board member John Clatterbaugh.
"The goal is to get a living specimen of every tree native to Maryland. The plants are permanently labeled. It's a learning lab for the kids. They'll be able to tell oaks from maples."
Clatterbaugh, 67, designed the tree-planting scheme and coordinated the purchases from local nurseries.
Another coordinator for the project, Forester Andrew Smogor, 35, of the Maryland Department of Natural Resources, directed the students as they worked.
Smogor said there was order in the arboretum because families of trees are planted in small groves.
Eventually, he said, a map identifying the types of trees will be produced for the students.
A $1,200 grant from the Maryland Department of Natural Resources - Forestry Service for the Chesapeake Bay School Reforestation Project funded the purchase of 25 different types of trees native to Maryland.
One final tree shipment is expected later this month. The first three trees from the grant were planted by the students on Arbor Day.