Mo. Rev. Stat. § 452.605

In an action for dissolution of marriage or legal separation involving minor children, or in a postjudgment proceeding wherein custody of minor children is to be determined by the court, the court shall, except for good cause, unless otherwise provided by local rule, order the parties to attend educational sessions concerning the effects of custody and the dissolution of marriage on children. As used in this section "good cause" includes, but is not limited to, situations where the parties have stipulated to the custody and visitation of the child, or a finding by a court with jurisdiction after all parties have received notice and an opportunity to be heard that the safety of a party or child may be endangered by attending the educational sessions. The court may order the minor children to attend age-appropriate educational sessions.