Qns. teen robs boy in school

An unhinged teen broke into a Queens middle school this week and robbed an 11-year-old pupil at knifepoint, then attacked a 51-year-old man outside the building, police said.

The terrifying episode unfolded on Wednesday at about 2:30 p.m., inside Robert A. Van Wyck JHS on 144th Street in Hillcrest.

The 5-foot-2, 110pound intruder slipped into the school, entered a bathroom and approached an 11-year-old male, cops said.

The young robber displayed a knife, pointed it at the victim’s chest and demanded money, police said.

When the frightened boy said he had no cash, the bandit took the victim’s water bottle and fled. The shaken victim was not injured, cops said.

It’s unclear whether the attacker attends the school.

Just minutes after the shocking incident, the attacker approached a man at 85th Road and 149th Street and began to argue with him, police said.

The knife-wielding assailant “began to lunge at the victim’s throat, but did not make contact,” cops said.

The teen slashed at the victim multiple times, cutting his jacket but not his body.

The teen then flung the stolen water bottle at the man and ran off. The victim was not injured.

The NYPD described the attacker as having a slim build, light complexion and was last seen wearing a black mask, a black hooded sweatshirt, a black jacket and black pants.

The NYPD on Saturday released a surveillance image (inset) obtained from a deli and a police sketch depicting the individual.