Wis. Stat. § 118.06: Flag, pledge of allegiance, and national anthem.

(1) Every school board and the governing body of every private school shall cause the U.S. flag to be displayed in the schoolroom or from a flagstaff on each school ground during the school hours of each school day.

(2) Every public school shall offer the pledge of allegiance or the national anthem in grades one to 12 each school day. Every private school shall offer the pledge of allegiance or the national anthem in grades one to 12 each school day unless the governing body of the private school determines that the requirement conflicts with the school’s religious doctrines. No pupil may be compelled, against the pupil’s objections or those of the pupil’s parents or guardian, to recite the pledge or to sing the anthem.