NEW YORK (CBSNewYork) -- There was both excitement and concern Monday as thousands of students returned to the classroom in New York City.
They had been shut down since last month, when the city's positivity rate reached 3%. But those metrics are changing, and so are the rules.
As CBS2's Hazel Sanchez reports, the first day back at PS 199 on the Upper West Side was a really good one for fifth grader Ian Rauch and his mom.
"It was incredible. I loved being back with my friends again," Ian said.
"I'm so happy. I hope it lasts as long as possible and everybody stays healthy," said parent Jessica Rauch.
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After being shut down for nearly three weeks, 850 schools reopened for preschool and elementary school students.
It was a little bumpy restart, for some.
"I couldn't really remember a lot of things, because online is really hard," said 9-year-old Cristina Wilson.
"I'm still afraid that I'm gonna get COVID," said second grader Annabelle Wilson.
"It's much better to be in school," said another mother.
It was a new day with a new plan, but the same mixed reviews.
"I'm not really too confident. I have a feeling they're going to shut down at some point again," parent Raymond Rosario said.
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"The teachers can be more sure if you're paying attention, and you can learn more in real school," her son added.
"There is no school without children. We need children in schools," said Miriam Petrovich, parent coordinator of the school's building response team.
The city scrapped the 3% infection rate threshold to close schools, and it's efforting to to maximize in-person learning by closely monitoring every school with aggressive weekly testing.
Most schools remain hybrid, but more than 150 schools have moved a full five days of in-person learning.
"And at this school they will be transitioning next week to five day a week learning, and that's what's happening at schools all over the city in the coming weeks," de Blasio said.
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Of the city's 1.1 million students, only 190,000 preschool and middle school students opted for in-person learning. They must have signed testing consent or a medical exemption to return.
"I am happy that the city has agreed to do more aggressive testing. Every school in New York City now will be tested -- 20% of the population inside the building will be tested on a weekly basis," United Federation of Teachers President Michael Mulgrew said.
Mulgrew said he believes the city does not currently have the capacity to test in all schools, so middle and high school students remain remote.
"I'm excited to go to school and I'm excited to do everything," said kindergarten student Sadri Brown.
"I'm a little nervous, I'm concerned about the social distancing but all and all I'm happy," said her mother Seniqua Brown.
"My hopes going forward is that we can all get tested so that way COVID can stop and we can go back in school knowing that we will be in there for a really long time," Ian said.
District 75 students return on Thursday. Many middle and high school students who opted for in-person learning are putting pressure on the city to reopen their schools. Mayor de Blasio says he's aiming to get middle school kids back in January, but high school students will be the last to go back.
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