Maggie Poston started the morning after her 90th birthday the same way she has nearly every day for the past 45 years: helping students at P.S. 282 in Brooklyn, N.Y. cross the street.

Locals know that the intersection between 6th Ave and Lincoln Pl is "Ms. Maggie's corner" — and to follow the rules of the road when she's on watch.

Poston started working as a crossing guard at P.S. 282 in 1978. "We haven't had any students hit by a car with Maggie here, because she makes sure that everyone stops," says Katerina Sidbury, P.S. 282's assistant principal.

Ida Ripo Ramos, Poston's supervisor and friend of 18 years, says she's never missed a workday. "No matter what's going on in her life, she shows up," Ripo Ramos adds. "She tells me, 'The kids need me.'"

Poston is a constant fixture in front of P.S. 282, keeping an eagle-eyed focus on the street. The only time Poston says she's been late was on Jan. 29, the morning after her 90th birthday. But Poston says she had a good excuse: She was up late the night before eating birthday cake with friends and family.

Wearing three layers of clothing, a reflective vest and frosted aviators, Poston greets almost all of the school's roughly 250 students by name as they enter the school. She's not a huge fan of hugs but is quick to dole out high-fives.

"It's not a bad gig," she says. "I just cross 'em and that's it."

Poston jokes that she stumbled into the job "by accident." She told her friends she was looking for a part-time job with a short commute, and one of them told her about the open crossing guard job. That friend, Poston recalls, even walked her to the police station for her job interview.

"I have no idea why I wanted to be a crossing guard, but I thought it could be fun," Poston recalls.

Although she's spent almost 50 years on the job, Poston says it hasn't changed much. "Nobody bothers me, I cross the kids and watch the traffic," she explains. "The years passed by so quickly, I didn't even notice … I just go to work and come home."

Even with the unpredictable weather and occasional reckless driver, Poston says being a school crossing guard is just as fun and rewarding as when she started. "I like keeping people safe, I like the routine of it and spending time in the fresh air," she says.

Poston lives less than a mile from the school in an apartment in Brooklyn's Prospect Heights neighborhood. She lives alone, but her four kids, five grandkids and five great-grandkids all live nearby.

She walks to work every day, and has maintained the same schedule since the 1970s: She helps kids cross the street from 7:30-10 a.m., hangs out at home while class is in session, then works again from 12:30-3 p.m. to help with the lunch rush and school pickup.

Poston says she gets a lot of visitors at work, whether it's her grandkids or former students who are all grown up and bringing their kids to P.S. 282 — even some police officers in the neighborhood say they crossed the street with Poston when they were younger. "She remembers all her kids," says Ripo Ramos.

The unwavering support and appreciation from Poston's co-workers and friends at the school have motivated her to continue working well past the typical retirement age.

On Jan. 29, the New York City Police Department surprised Poston with a birthday party during her lunch break. At the party, Poston told her friends that she intends to retire in June once the school year ends.

"It ran up on me," Poston says of turning 90 and retiring. "But I guess it's a good reason to celebrate."

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