Fourth graders at Westridge Elementary School in Provo might not be able to go to Utah Lake for their annual field trip this year. So they’re doing something to help clean it up.

The fourth-grade classes usually get a grant to go on a field trip to the lake in the spring. But when the school applied for the grant this school year, the teachers heard they might have to defer the trip because of the lake’s algae problems.

The students have a unit on water filters, and the teachers realized this would be an opportunity for the students to tackle a real problem.

“That’s the fun thing about this project,” said Kimberly Sessions, a fourth grade teacher at Westridge. “A problem like this that affects the community doesn’t just have to be left up to the adults.”

The students are creating water filters out of plastic liter bottles to clean up the water. They’re using real water from Utah Lake to test out their products.

“It doesn’t smell good,” said Brooklyn Sturdivant, a 10-year-old student in Sessions’ class.

Brooklyn’s group made a filter that includes a nylon and cotton balls. After testing it once, the students had a chance to improve on their designs.

For Brooklyn’s group, that meant changing the design so it removed the smaller things in the water, like pieces of algae.

“I think my team and I did a good job at getting the big stuff,” Brooklyn said.

Their plan was to add cotton balls to the design.

The teams were given the goal of filtering the water quickly with an inexpensive design. Before building their filters, the students looked at the water under the microscope. They wanted the water to look cleaner, but to make it safe as well.

The first filter 9-year-old Henry Wallin’s team made didn’t work so well. It used two coffee filters, which broke when water was put in and rocks fell through them. Their model also uses a nylon to filter the water.

They were taking what they learned from the first test to improve their design.

“It always doesn’t work as well the first time and works the second time,” Henry said.

The students are writing letters explaining what they’ve learned from the project. In May, they might be able to visit the lake.

For the students, they’ve been putting more effort into the project because it’s a real-world problem.

“They’ve been pretty excited about that,” Sessions said.