when my son was 12 we had a party at my house and a boy took a pricey new pair of runner from the shoe pile and left his old pair. we did not notice till all the boys were going home - the mother of the son of the stolen shoes called the school and the principal had a quick chat with the thief the next day at school and he was told to give the shoes back or else- so the boy came back to our house and gave me the shoes - he said I am sorry to me and I gave them to the boy missing the shoes- I think I was easier to deal with me than the mother of the stolen shoes son, but I was so glad the mother called the principal and the school got involved - can you call the principal without calling the police, as she/he knows the child involved, and can manage the situation better