A record shall be kept indicating the legal custodian of each pupil. Such custodian shall be responsible for informing the Board of Education of any change in the pupil’s guardianship. If one parent/guardian has been awarded custody of the pupil in a divorce settlement, the other parent/guardian shall present to the Director a letter permitting that person to accompany the child to or from school. The Director must take such steps as deemed necessary to ensure that the child is released only to the proper adult guardian.