California
Education Code § 35292.5
(a) Every public and private school maintaining any combination of classes from kindergarten to grade 12, inclusive, shall comply with all of the following:
(1) Every restroom shall at all times be maintained and cleaned regularly, fully operational and stocked at all times with toilet paper, soap, and paper towels or functional hand dryers.
(2) The school shall keep all restrooms open during school hours when pupils are not in classes, and shall keep a sufficient number of restrooms open during school hours when pupils are in classes.
(b) Notwithstanding subdivision (a), a school may temporarily close a restroom as necessary for pupil safety or as necessary to repair the facility.