Call it recycling with a purpose -- with the purpose being fun as well as educational.

Students from several central Ohio schools -- including Herbert Mills Elementary School, Waggoner Road Middle School and STEM Middle at Baldwin Road in Reynoldsburg -- participated in the Cardboard Challenge last week, using cardboard to create everything from letters to roller coasters.

Other central Ohio participants included Evening Street and Worthington Hills Elementary schools, Indian Run Elementary School in Dublin, Darby Creek Elementary in Hilliard and Wickliffe Progressive Elementary School in Upper Arlington.

Sponsored by the PAST Foundation in partnership with the Columbus Museum of Art, the Oct. 7 event asked students to become designers and inventors, said Lori Trent, from PAST.

"Throughout the day, students are encouraged to use creative thinking to respond to challenges using only cardboard, tape and other recyclables," she said.

Mary Ellen Weeks, principal at Herbert Mills, said teachers invited parents to view the cardboard creations Oct. 5 at the elementary school.

"The Cardboard Challenge is a way for our students to demonstrate what they have learned in the classroom by allowing them to use their creativity and our design cycle to build something unique out of cardboard," she said.

The challenge was built into the curriculum at Herbert Mills this year, becoming an end-of-quarter assessment in every grade, Weeks said.

"The constraints were really dependent on the grade, though the materials used were limited to cardboard, tape, paint and marbles and straws in some grade levels," she said.

Kindergarten students created cardboard letters; first-graders used force and motion standards from their science classes to create mazes and second-graders used measurements, along with force and motion standards, to create rollercoasters.

Weeks said third-graders focused on the question, "How does the past influence the future?"

"Their social studies standards focus on Reynoldsburg history, so they interviewed residents that had been part of the city for roughly 50 years, as well as representatives from the city planning office," she said.

She said the students built a 3D coordinate map of Reynoldsburg as it might look 50 years from now.

Fourth-graders used measurements and social studies standards to showcase Ohio history, building monuments that can be found all over the state.

"They included a placard above each monument, with a picture and a QR code that links back to a student-created presentation on that monument," Weeks said. "The students and teachers did an amazing job on these -- I am very proud."

Trent said PAST is a nonprofit foundation that has been a leader in designing STEM education across the nation for the past 17 years. STEM stands for science, technology, engineering and mathematics.