BOSTON (CBS) – The Massachusetts Department of Elementary and Secondary Education has sent a new letter to superintendents suggesting how the state’s new color-coded coronavirus map should play a role in school reopening decisions.

The update could have a late impact on what districts and charter schools across Massachusetts decide to do in September. Their final fall reopening plans are due to be filed with the state on Friday. Many are debating between a hybrid model or going fully remote.

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Governor Charlie Baker unveiled the color coded map Tuesday identifying community risk with the colors red, yellow, green and white, with red being the highest risk and white the lowest.

According to a letter from Education Commissioner Jeffrey Riley sent to school leaders after Baker’s announcement, red would mean remote learning for a town, yellow a hybrid version and green and white would be full time, in-person classes for students,

(Image credit: Mass. Dept. of Education – click to enlarge)

As of Wednesday, only 33 communities were in the red and yellow zones.

“It is our expectation that districts’ learning models will follow this color-coded metric unless there are extenuating circumstances identified after consultation with local boards of health,” Riley wrote.

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“We understand that local school committees and governing boards, working with district and school leaders, have recently finalized or are about to finalize initial fall reopening plans. We expect these updated metrics and related guidance will support your decision-making both for school reopening and throughout the year if we encounter changing circumstances.”

“We would certainly hope that, based on this data, if you’re in a green or a white community, I can’t imagine a good reason not to go back – whether it’s full time or in some sort of a hybrid. Because for all intents and purposes you meet all the benchmarks that are being used across the country and across New England to make decisions about whether it’s safe to go back to school,” Baker said Tuesday.

“All of the guidance that was developed by DESE and distributed to schools and school districts was done with the Department of Public Health and the American Academy of Pediatrics here in Massachusetts,” Baker said. “It’s a good set of guidance. It’s the right kind of advisories, and contextually those communities are in a perfectly appropriate place to have kids back.”

Each district submitted three preliminary plans last month – one for all remote, one for all in-person and one hybrid model. Just last week, Baker said he was against schools starting all remote.

But several communities have recently decided to start the new school year fully remote and the state’s two largest teachers’ unions want it as well.

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The Massachusetts Teachers Association doesn’t believe it will be safe until school buildings are upgraded to improve air quality and there is contract tracing and testing available.