GREENSBORO, N.C. — It's back to school time and that means new backpacks, recycled backpacks and hand-me-downs!

When it comes to the recycled and hand-me-down backpacks, you don't just need to clean them out from last year, you need to wash them. Think about it. They've been under the seats of the school bus, on the sidewalk and don't forget the school bathroom floor. Ewwww.

READ: 1ST DAY OF SCHOOL. BE CAREFUL WHAT YOU POST!

Watch as deputies test bulletproof backpacks

You can't just put a backpack in the washer with all the straps, buckles, zippers. They can get caught in the machine.

We found a solution on Lifehacker. A pilllow case. Put the backpack in the case. Tie it up and put it in the washer on the gentle cycle. Then air dry the backpack.