Be nice, this is my first model!
This adjustable shelf is designed to fit any personal locker, with a width ranging from 8.5" to 15" wide, 8" deep, and legs that make it 10" tall. Two 12x3mm magnets are inserted in each of the top halves during the print to help the shelf stay attached to the left and right sides of the locker.
I have not stress tested it, but it should handle a reasonable load of books & school accessories without trouble. Printed in PLA, but feel free to remix and try any other filament.