CHICAGO (CBS) — It was time to let them go.

Students raised trout in their classroom and set them free into Lake Michigan.

They are first and fifth graders from Gems World Academy. The young scientists have been studying water and beach conditions for the best spot for their trout.

“We picked site A because there were so many rocks for shelter and there wasn’t that many predators,” said first grader Sophia Tucker. “Maybe they’re going to swim to Michigan to see other friends.”

Aside from raising the fish, the students also built underwater remote controlled machines to monitor the animals in the water.