Is it permissible for a teacher to take leftover candy from children in kindergarten when its owner is unknown?

The object that must be announced is that which a person of its owner would follow—that is, something of value. As for something trivial and worthless, it is permissible to own and benefit from it without announcing it, if its owner cannot be identified. The criterion for determining what is trivial from what is not is common practice (urf).

A valuable lost item, if it is food that remains, may not be eaten until after a year. If it is something that does not remain, the finder has the choice between eating it or selling it and keeping its price. If its owner is identified after it has been eaten or sold, the finder must compensate him for its value or return its price to him.