The provisions of detention or an in-school suspension program for student violations of policies, rules and procedures shall provide principals with an additional alternative for dealing with disciplinary problems that occur in the schools. When this alternative is appropriate, students will be assigned to serve a specified time period in the in-school suspension program. These assignments, and the determination of the time period for them, shall be determined by the principal, or his or her designee.

§ 160.261, RSMo