It may be a cubby or a locker where they store their coats and other belongings during school hours. You can transfer to your house what your child is learning at school about keeping track of his things. Help your child organize his space at home. You can use boxes of any kind, small enough for him to handle.
Shoe boxes are excellent for small toys and art supplies.
Larger boxes or baskets will handle the big items. A laundry basket is great for the stuffed animals. Together, label the boxes. Print in large letters with a marking pen. He may be able to do some of the printing with your help.