What should I do about money I stole in my youth, for which I have repented, but I do not know its amount or its owners, and I cannot return it to them directly?

There is no sin upon a teenager for committing prohibitions, due to the Hadith regarding the lifting of the pen from three. However, he is liable for what he damages or steals. The questioner must return what he stole to its known owners without informing them of the theft. He should give in charity what he stole from those he does not know. He should act based on his best judgment in estimating the amounts, because best judgment takes the place of certain knowledge when there is inability.