All those theories about Wednesday’s mystery UFO sightings over Manhattan are about to go “pop.”

A Westchester elementary school believes the puzzling orbs floating over Chelsea were likely a bundle of balloons that escaped from an engagement party they held for a teacher.

“UFO? They’re crazy – those are our balloons!” said Angela Freeman, head of the Milestone School in Mount Vernon. “To me it was the most automatic thing. But it’s all over YouTube.”

A parent was bringing about 40 iridescent pearl balloons to the school for language arts teacher Andrea Craparo when the wind spent a bunch away around 1 p.m.

“They looked big and they were all together, so it looked like one UFO,” said fourth-grader Nia Foster, 9.

Awestruck gawkers began calling the NYPD and the FAA starting about an hour later when mysterious flying objects appeared over Manhattan.

Meteorologists with the National Weather Service said the wind was blowing south at 5 to 10 m.p.h. at the time which would make the engagement balloon theory possible.

Police have said they believe the puzzling objects were likely balloons.

The sky was very clear at the time, making high-flying objects extremely visible from the ground.

Also, helium-filled balloons tend to change shape at high altitudes as the gas expands – making them look abnormal from below, experts say.

As with anything related to the paranormal, other possibilities abound. Following with the balloon theory, some suspected an event in Times Square where a number of yellow balloons were released to celebrate a joint-tourism agreement between New York and Madrid.

Then there is author Stanley Fulham, a retired NORAD officer who recently published a book predicting the world’s major cities would be visited by UFOs on Oct. 13.

He did not return calls – and there was no word on his whereabouts.