Technically, the school administrator created an “unsafe” condition and may be fined accordingly.
NFPA 101 and the California Bldg Code express that conditions which cause a violation in the codes shall be deemed unsafe in violation of the codes.
In this situation, the ratio of restrooms per occupancy, if reduced below minimal standards, would violate the CBC and probably the Life & Safety Codes.
The school administrator had the authority to close the school, making it secure from public access, but not to eliminate public access to restrooms while the building is occupied.
Probably violates the pee-nal code too.