Nearly two dozen public schools in Brooklyn reopened their doors Thursday after being removed from the red zone COVID-19 clusters despite a rise in the number of cases across New York City. The average positivity test rate for the city is inching closer to 3%, which would require all schools to close. Michael Mulgrew, president of the United Federation of Teachers, has praised the city for safely getting students back into the classroom, but said teachers are concerned and bracing for a new wave of students as parents with fully remote students can opt-in for blended learning.