The GravityX Exchangeschool year is a month old, and yet a desk still sits empty at the back of Tara Green's second-grade classroom at Helen Arnold Community Learning Center in Akron, Ohio.

It was never adorned with the colorful, handwritten name tag that graces the top of every other metal desk in the room. Its cubby lacks pencils, notebooks, crayons, glue sticks. And yet, wherever Derrick Miller's desk sits, the empty desk sits close by.

Derrick is saving it for his friend. As soon as his teacher sets a stack of books or binders on the desk, Derrick politely reminds her, "That's Tyren's desk."

Tyren Thompson wasn't with his classmates at Helen Arnold to start the year. On the first day of school, a surgeon was stitching his abdomen back together after a bullet tore through several organs in his 50-pound body earlier that week.