The Centers for Disease Control and Prevention on Friday recommended that schools fully reopen for in-person instruction this fall, further paving the way for a return to a normal school year.

“Students benefit from in-person learning, and safely returning to in-person instruction in the fall 2021 is a priority,” the federal agency said.

The guidance suggested that ensuring some mitigation measures — like social distancing — shouldn’t keep children from returning to classrooms full-time. But it also advised schools to take other steps, like requiring unvaccinated children and staffers to wear masks — a topic that has fueled a fraught debate in districts around the region, and one that some predicted would intensify.

“The whole discussion is going to be around masking for elementary kids in the fall,” West Chester Area School District Superintendent Jim Scanlon said Friday.

School districts across the region had been awaiting the guidance as they plan for the fall. The Pennsylvania Department of Education said earlier this week that it would align its recommendations to the CDC’s.

Navigating COVID-19 measures for schools has been a frustration across the region and the country since the start of the pandemic, with sometimes confusing or conflicting policies and recommendations from officials and health experts. A vast number of schools remained closed and turned to remote classes last fall, even as critics complained it was a less effective way to learn or noted how the coronavirus proved to be far less severe in children than adults.

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The federal agency is continuing to call for safety measures but is leaving the door open for schools to reach their own decisions. For instance, its guidance still recommends 3 feet of distancing between students in classrooms, but acknowledges that may be complicated to achieve in districts with more crowded buildings.

“When it is not possible to maintain a physical distance of at least 3 feet, such as when schools cannot fully reopen while maintaining these distances, it is especially important to layer multiple other prevention strategies, such as indoor masking,” the CDC guidelines said.

In Philadelphia — where district officials had said the school system would not be able to fully reopen if 3 feet of distancing between students was required — spokesperson Monica Lewis said Friday that officials are “excited about the full reopening of schools and welcoming students and staff back to 100% in-person learning, five days a week for the 2021-22 school year.” The district didn’t offer full-time in-person instruction last year, and 10th through 12th graders didn’t return to classrooms at all.

Lewis said the district will work with the city health department to determine masking and distancing rules within schools. While the department’s current guidance still calls for 3-foot distancing, that is “a recommendation, not a requirement,” Lewis said.

Philadelphia Health Department spokesperson James Garrow said officials will monitor COVID-19 case counts over the summer, and if they continue to drop and vaccine rates keep rising, it could “allow us to further relax restrictions like the 3-foot physical distancing in schools.”

The news had many parents cheering, particularly those who have been advocating for fully reopened schools. “We’ve been waiting for this,” said Priscilla Lo, whose children attend Philadelphia public schools.

The CDC also recommended that unvaccinated children and adults continue to be masked in schools, including children under 12 who are not yet eligible for the vaccine.

In New Jersey, Gov. Phil Murphy said late last month that the state would not require students to wear masks in school come fall.

Many Pennsylvania school districts — which are currently running expanded summer programs with the help of federal pandemic aid — dropped their masking requirements with the expiration of the state mandate on June 28. But they were instructed this week by the state education department to now require students to wear masks on buses, based on a federal order requiring masks on public transportation.

Marc Bertrando, superintendent of the Garnet Valley School District in Delaware County, said the new CDC guidance means masking will become the central issue facing his district; its current plan calls for no masks in the fall. He’s waiting for the state to weigh in.

“We want to make sure we give it enough time and don’t make any rash decisions until we’re closer to the beginning of the school year,” he said Friday. The superintendent said that even with his own kids, “nobody’s really masked in our area.”

» READ MORE: School mask requirements are coming under fire as parents ramp up pressure on districts

Maggi Barton, a spokesperson for the state health department, said it was reviewing the recommendations with the education department and “will provide any needed associated guidance to schools next week.”

Case rates in the region have remained low as vaccinations continue to increase. Yet officials are watching the rise of the fast-spreading delta variant — not yet dominant in the Mid-Atlantic, but making up more than half of new cases nationally.

How exactly schools would assess shifting rates wasn’t immediately clear Friday. Last year, many in the Philadelphia region turned to their county health departments.

Bucks County Health Director David Damsker said Friday he agreed with the CDC’s assessment that schools should fully reopen, but not its recommendation for continued masking.

”Schools should not have to follow any guidance that distracts from the learning process,” said Damsker, who last month advised Bucks districts they could drop mask requirements before the state’s mandate had expired. “Schools should be in person, schools should not require masking, schools should get back to teaching kids. COVID does not hurt children, for all intents and purposes. What [the] CDC is doing is continuing the COVID treadmill for students, and that needs to stop.”

He also took issue with testing asymptomatic schoolchildren for COVID-19. ”Now that we have an effective vaccine, we need to treat this like a chronic disease, like influenza,” Damsker said.

A spokesperson for the Chester County Health Department — which is also serving Delaware County until next month — did not immediately respond to questions about the CDC guidance. A Montgomery County spokesperson said the health department was still reviewing the guidance.

Like a number of area suburban districts, West Chester has been planning a fall opening “as normal as can be in a post-pandemic era,” Scanlon said. Its plan doesn’t require 3 feet of spacing, though having enough room isn’t a particular challenge for the district, he said.

In the Cheltenham School District, interim superintendent Nancy Hacker also said the CDC’s guidance is helpful but does not alter the district’s planning for the fall.

“At this point, we fully recognize the traumatic toll that a year with either no or limited schooling has had on our students and families,” Hacker said. “We fully intend to try to fully open in September and get our kids back into classrooms.”

Cheltenham is still finalizing its health and safety plan, but Hacker said it’s likely she’ll recommend social distancing measures where possible.

“We know that with full student bodies back in those schools, it may be challenging in some areas,” Hacker said. The district is not planning at this point to require masks, she said, but students can choose to wear them.