The group marched from the United Federation of Teachers Headquarters to the New York City Department of Education offices in Lower Manhattan.
They say they simply don't feel safe.
"I can reach the maximum amount of students if I'm doing it from home. I know it's super inconvenient, but that would be the safest thing for everybody right now," teacher Gladys Paspera said.
The protesters pushed back against de Blasio's plan for a hybrid schedule, where some days students are in class while other days they are online.
"I want to go, but I don't want to do something that could risk people's health," student Rufus Shaffner said.
MORE: NYC submits 'outline,' not reopening schools plan: Cuomo advisor
One of the big issues among the protesters was the lack of ventilation in schools, they say many classrooms don't have air conditioning and windows often don't open.
"We don't have a cure, we don't have a vaccine for COVID and I don't think the plans that have been presented by the mayor or the chancellor are safe," parent Dr. Kaliris Salas said.
The mayor insisted decisions were based on safety first.
"We will not open schools unless we are below a three percent citywide infection rate. If we ever go above that for a seven day period, we're going to close schools," de Blasio said.
Teachers complain that the COVID testing included in this plan is too long of a delay to learn the results. So if it comes back positive, that student or faculty member will have already infected the school population.
"I don't care what any bureaucrat says. I trust the parents more than anyone and I don't care if a school district says 'reopen.' If they don't have a good plan for reopening, no kids are going to come. No teachers are going to come," Gov. Andrew Cuomo said.
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