Missouri - Firearms/Weapons on School Campuses: Prohibitions or Restrictions
Missouri Revised Statutes 160.261 Discipline, written policy established by local boards of education
5. The policy shall provide for a suspension for a period of not less than one year, or expulsion, for a student who is determined to have brought a weapon to school, including but not limited to the school playground or the school parking lot, brought a weapon on a school bus or brought a weapon to a school activity whether on or off of the school property in violation of district policy, except that:
(1) The superintendent or, in a school district with no high school, the principal of the school which such child attends may modify such suspension on a case-by-case basis; and
(2) This section shall not prevent the school district from providing educational services in an alternative setting to a student suspended under the provisions of this section.
6. For the purpose of this section, the term “weapon” shall mean a firearm as defined under 18 U.S.C. Section 921 and the following items, as defined in section 571.010: a blackjack, a concealable firearm, an explosive weapon, a firearm, a firearm silencer, a gas gun, a knife, knuckles, a machine gun, a projectile weapon, a rifle, a shotgun, a spring gun or a switchblade knife; except that this section shall not be construed to prohibit a school board from adopting a policy to allow a Civil War reenactor to carry a Civil War era weapon on school property for educational purposes so long as the firearm is unloaded. The local board of education shall define weapon in the discipline policy. Such definition shall include the weapons defined in this subsection but may also include other weapons.