NEW YORK (CBSNewYork) — The demand for COVID-19 vaccines for kids is higher than expected in New York City, but Mayor Bill de Blasio says that’s a good thing.

On Monday alone, roughly 4,500 kids ages 5 to 11 were vaccinated at their schools.

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CBS2’s John Dias found long lines Tuesday morning outside Public School 87 on the Upper West Side.

“I’m a little bit tired of it,” first grader Maisie Bovey told Dias.

“I think it’s boring,” 10-year-old Julien Reynal added.

Some kids may have been annoyed while they waited for their shot, but many parents said it was time well spent, especially after almost missing out on the opportunity.

“Even if we don’t do the line here, we will do it anywhere else,” said one parent.

“Might take up to three or four hours, they said. But for the vaccine, it’s worth it,” another parent added.

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Initially, parents were told 100 students could get vaccinated at the school. Then, less than an hour after the pop-up clinic opened, more than half of them were turned away.

“It was, at first, not organized,” Upper West Side mom Morana Mesic said.

Mesic’s 9-year-old son was the last one to make the cut.

“A lot of them tried to find out if there’s anywhere else in the neighborhood to get it,” she said.

“We had seen a pop-up van on the other block, so we went running over there and tried to get in line there. Their nurse was running late,” said Upper West Side mom Rosemary Andress-Sanborn.

“We went to the Natural History Museum,” her daughter added.

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Then, luck was on their side. The school sent an email to apologize and let parents know the team could vaccinate up to 100 children if time allows, which meant the line grew even longer.

“So we came rushing back, and now we’re here,” Andress-Sanborn said.

COVID VACCINE

The confusion came following plenty of rollout hiccups on Monday. On the first day the clinics opened, many sites didn’t have enough supply. The mayor said the city based the anticipated supply on the previous demand for kids 12-17, but they didn’t match up.

“There were some places where we had to do better and we had to get supply to them and get additional help, and we did that,” de Blasio said.

He said this is a good sign, though, and it’s promising that parents are embracing the shot. Now, the city is trying to make up for the higher demand.

“Today, we’re going to have 24 mobile vaccination units out at schools around the city where we think demand will be high, we’ve added additional vaccinators, additional staff,” he added.

Meanwhile, over at Public School 1 on Staten Island, CBS2’s Alice Gainer saw no line. The principal told her the school wasn’t having any issues with supply, but wouldn’t say how many kids got the shot, either.

She also didn’t notice any issues in the Bronx.

City leaders said having school sites are just a small part of the vaccination puzzle.

“We know that many parents will be most comfortable getting their kids vaccinated at a pediatrician whom they trust,” city Health Commissioner Dr. Dave Chokshi said.

As it stands, roughly 25,000 kids ages 5 to 11 in the city have gotten their first shot since Thursday — the first day it was made available to them. There are an estimated 660,000 schoolchildren in that age range across the five boroughs.

The mayor said if a child could not get vaccinated Monday or Tuesday because of lack of supply, there would be another site for them at their school again in the next few days.

Parents and guardians with questions about the vaccine are encouraged to call 212-COVID19. Visit nyc.gov/vaccinefinder to schedule an appointment and schools.nyc.gov/covid19 to see when shots will be offered at schools.

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CBS2’s Alice Gainer contributed to this report.

John Dias