Wyoming constitution
Article 7: education; state institutions; promotion of health and morals; public buildings
Section 12

No sectarian instruction, qualifications or tests shall be imparted, exacted, applied or in any manner tolerated in the schools of any grade or character controlled by the state, nor shall attendance be required at any religious service therein, nor shall any sectarian tenets or doctrines be taught or favored in any public school or institution that may be established under this constitution.