Yitzchok2:
I disagree, and strongly so. Having observed this practice for years, it is clear that it can be done in a manner in which it is educational. That is what I would want for my child. That rebbe returns the item, either at the end of the day or week, or to the parents. Keeping the item is unquestionably ????. Even if you remove the technicality of it via contract (if that actually works), it is still bad chinuch. It is punishing, not educational, and that is NOT called chinuch.
Your other point is simple fantasy. You noted that your parental wish for your child’s best education is also that of the rebbe. I beg to differ. That is not a given anymore. Just how many rebbes in classrooms do you know who deicated their lives to continuing the transmission of Torah? Inquire a bit more, and discover that the overwhelming majority entered the field out of lack of capability of being eligible for other fields. Backing into chinuch sometimes works, where the awe of the task generates some internal motivation. But that does not explain the lives of a huge percentage of rebbes and teachers, who just need a job and a salary. I know this sounds like sour grapes, but the frequency of interaction I have with the education field plus the parents, like me, who patronize it, makes optimism harder to grasp.
It is also alarming to watch the development of stricter and more abusive forms of “discipline” while the chinuch system tries so hard NOT to be mekarev the talmidim to connect them to the chain of transmission of Torah. Read through the contracts with yeshivos. Does the document highlight the responsibilities of the yeshiva to make your child feel nurtured and encouraged to progress in Torah based growth, or is the bulk of the terms forms of retribution for breaking rules? I read through many such contracts, and they are sickening. They reveal an attitude that bears no resemblance of what our leaders wanted chinuch to represent.