For Aaron Green, a stop at the toy store is part of his routine this holiday season.

The Columbia University student isn't shopping for friends or family. Instead, he's picking out gifts for children he's never met: a Lego set for a little boy and a doll for a young girl, all destined for Toys for Hospitalized Children.

"It's really amazing to see the light on a kid's face and in their eyes when you bring them a toy and play with them, and it can really make their day," Green told CBS News New York's Hannah Kliger as he browsed the shelves.

Green said he decided to get involved after watching his sister's spirits lift during a hospital stay years ago, when volunteers brought music and toys to her room.

"It really was an amazing experience for her. And they came in, sang songs with her and played guitar, and it just made her feel so much better," he said.

Go Locker's role in bringing holiday cheer

After shopping, Green drives a few blocks to a Go Locker location in Borough Park. With a few scans on his phone, a locker door clicks open, accepting his donation.

Nigel Thomas, founder of Go Locker, says the idea for the partnership with TFHC grew out of Thomas' own experience welcoming a child while surrounded by families facing much harder circumstances.

"My wife and I, we brought into the world a baby girl and while we were at the hospital, there were some other folks that were not in great situations. And I thought to myself, well, 'good Lord, what can we do to make life better?'" Thomas recalled.

Thomas said he wanted to find a fast, free and accessible way for people to donate toys throughout the city. His Brooklyn-based company was the perfect solution.

"Our lockers are micro storage devices, and it could be used for much more than just transactional needs," he said.

There are now more than 70 Go Locker locations across New York City, most of them in Brooklyn. Toys dropped off at the lockers are sent to a distribution center before being delivered to hospitals.

"It brings joy to the children"

At Maimonides Medical Center, 4-year-old Alan Tcherevatenko was feeling shy during an overnight stay following a medical emergency. That changed when JJ Hecht from Toys for Hospitalized Children arrived carrying a giant set of Legos, quickly capturing Alan's attention.

His father, Stan Tcherevatenko, said the impact goes beyond a moment of fun.

"It brings joy to the children as well, which can help them get better," he said.

Hecht said that emotional boost is central to the organization's mission.

"We believe that a positive outlook really helps a child forget about the illness, not to get stuck in it, but rather to go above it and really get better," Hecht said. "We're partnering with a dozen hospitals in New York City and 36 hospitals nationwide this holiday season. And we will be delivering 30,000 toys that children all across the country."

Founded in 1953, Toys for Hospitalized Children works year-round, but the holiday season marks its largest push. This year, thanks in part to the locker partnership, thousands more toys are expected to reach children's hospital rooms.

As donations continue to roll in, organizers say each locker door unlocks a moment of joy for a child who needs it most.

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