Traditionally, it is seen as the father's role and sometimes the mother's role, an elder brother for a younger brother, or an elder sister for a younger sister. On the other hand, the truth is the one who is better qualified and more experienced should set the limits for the one who is less qualified and less experienced. In terms of religion, the one with stronger faith and righteous deeds should set limits for the one who has less, regardless of age. Sometimes it is seen that the parents are less practicing Muslims than the children themselves. In that case, the children should advise the parents.
Teachers have a much greater role to play.
However, the limits should be taken in the light of permission and responsibility from God. Know the teachers personally and interact with them. Neglected children expose themselves to various abuses. Supervise their homework. Watch TV with your children and select good educational and entertainment programs.