What is the ruling on the action of a girl who took a small sum of money she found in a box hanging at school, then repented and gave the money in charity on behalf of its owner, while the school still exists?

The girl must sincerely repent for taking the forbidden money. If she knows the owner, she must return the money to him or to his heirs. If the owner cannot be identified, she must give it away in charity on his behalf. If the money belongs to the school, she must return it to those in charge. If that is not possible, she should donate it for the general welfare of the Muslims.