This marks the fourth year that the students have done the challenge.

Students at Lake Orion High School lined up on Friday to turn in...not their homework, but their cell phones. For every phone that was bagged and turned in, one dollar was donated to Cell Phones for Soldiers.

It's an organization that buys minutes for active duty service members to talk their families. They've provided more than 300 million minutes, as well as helped out over 30,000 veterans with emergency funding. They're also committed to recycling cell phones to reduce the effect on landfills.

The phones are bagged and labeled, and the students receive them back at the end of the day. A small sacrifice, considering what the military members give up every day. Nice job, Lake Orion students!