Cape Elizabeth public schools will reopen in September under a hybrid model that will allow children to study entirely at home or attend classes half-time in an effort to keep students and staff members safe during the coronavirus pandemic.

The School Board voted unanimously Tuesday to approve the hybrid model after putting to rest concerns raised last week about faulty ventilation systems in the town’s aging high school, middle school and elementary school.

A rolling opening starts Aug. 24 for teachers and continues through September.

“It’s literally impossible to make everybody in the community happy,” board member Laura DeNino said during the online meeting.

But with such low COVID-19 infection rates in Maine, DeNino said, “if we can’t open, who can?”

To prepare for and welcome students in phases, teachers will return Aug. 24-Sept. 3, students will return in small groups the following week and instruction will resume with a “hard start” on Sept. 21, Superintendent Donna Wolfrom said.

Wolfrom said the district is committed to providing a safe educational environment during the pandemic. The plan calls for a wide spectrum of logistical and instructional changes, such as improving ventilation, sanitizing buildings diligently, requiring health screenings, mask-wearing, social distancing and regular hand-washing, and allowing teachers to hold classes outdoors as long as weather permits, including in a tent outside the high school.

Ventilation concerns cropped up during a five-hour board meeting on Aug. 11 as members discussed the hybrid reopening model, which gives students the option to attend in-person classes two days per week with the remaining days dedicated to remote learning, or learn at home 100 percent of the time.

The board delayed its vote after Facilities Director Perry Schwarz said he was concerned that poor ventilation systems in the three schools would compound the risk of spreading COVID-19 among students and staff.

Schwarz said there was no hallway ventilation on the first and second floors of Cape Elizabeth High School and ventilation in the hallways of the middle and elementary schools was inadequate for the traffic they carry. He also noted several unventilated spaces that have been repurposed for instruction.

Ventilation problems in each school were outlined in a building-needs assessment report prepared last September by Colby Company Engineering and Scott Simons Architects, both of Portland. The report concluded that the ventilation systems are “nearing or beyond their useful life expectancy and should be scheduled for replacement in the near future.”

Cape Elizabeth High School was built in 1969. Cape Elizabeth Middle School and Pond Cove Elementary School are in a complex including an original 1934 building with additions and renovations following in 1960, 1962 and 1994.

On Tuesday night, Schwarz said he reviewed blueprints of the high school’s ventilation system and discovered the hallways have existing duct work and fans that had been shut off in past years, perhaps because they were too loud.

After refurbishing the hallway ventilation equipment, Schwarz said, the air quality in the high school “is going to be better than it ever was.”

Schwarz also said ventilation in the middle and elementary schools meets government standards and any unventilated spaces will no longer be used for instruction.

Elizabeth Yarrington, a teacher at the high school, told the board that staff members realize remote learning isn’t ideal, but they believe the safety of students and staff members must remain a priority.

In July, Gov. Janet Mills issued guidance for school districts to decide how to resume instruction this fall based on recent infection rates showing the risk of COVID-19 is relatively low in Maine.

Mills said schools in all 16 counties could reopen if they could meet six requirements: symptom screenings before coming to school; physical distancing within school facilities; everyone wearing face coverings; practicing proper hand hygiene; wearing personal protective equipment when in close proximity to students; and isolating at home if sick until meeting criteria to return to school safely.