DES MOINES, IOWA — Mayor de Blasio said it’s “unacceptable” that kids at a Queens high school openly smoke weed, thanks to a principal who, as The Post reported Sunday, isn’t enforcing the rules.

“If something like that is happening there will be serious consequences for anyone involved,” Hizzoner said from Iowa.

“It is not legal and it’s not acceptable.”

Fuming teachers at Forest Hills HS told The Post that there’s a strong scent of pot in classrooms and hallways as kids smoke and vape away.

One educator reported the smell being so pungent one day that “you could taste it on your tongue.”

Educators placed the blame on principal Ben Sherman, who they said shrugs off the on-campus puffing because marijuana is “going to be legal soon,” anyway.

De Blasio blasted the situation as “unallowable and unacceptable.”

Marijuana is banned in all schools but under a new DOE program, cops or safety agents may give kids 16 or older a “warning card” instead of a summons.

Sherman referred questions from The Post to DOE spokesman Doug Cohen who called the principal “an effective leader” and said they take complaints seriously.

Additional Reporting by Tamar Lapin