A day after one of the nation’s largest school systems announced its proposal for fall learning, teachers within Fairfax County Public Schools rose in revolt and refused to teach in-person, as the plan demands, until officials revise their strategy.

Fairfax Superintendent Scott Brabrand had announced a hybrid learning program — one of the first concrete strategies released by schools nationwide — in an email to parents Wednesday. Under the plan, he wrote, families in the Northern Virginia district, which serves 189,000 students, would be able to choose between 100 percent virtual learning or part-time in-person schooling.

Schools nationwide abruptly switched to distance learning this spring amid the coronavirus pandemic. Now, they are seeking ways to safely open for the upcoming school year.

In the first enrollment option, Fairfax County students would receive “virtual, interactive instruction” four days each week, without ever setting foot on campus; in the second, students would attend bricks-and-mortar schools for face-to-face learning at least two days a week. Brabrand wrote that Fairfax families and teachers must choose an option by July 10.

The plan drew criticism from some parents and educators almost immediately for a lack of specifics. Late Thursday, the three major teachers’ associations in Fairfax issued a stark rebuttal, writing in a joint statement that the plans for face-to-face teaching imperil teachers’ health and that officials failed to provide sufficient time for families and staff members to make their decisions.

The three groups — the Fairfax County Federation of Teachers, the Fairfax Education Association and the Association of Fairfax Professional Educators — are asking their members to select the distance-learning option, en masse, until administrators work with association leadership to develop more detailed plans that better prioritize the safety and well-being of students and staff members. The teachers’ resistance previews the kind of backlash administrators throughout the country may encounter as they ask their workforce to return to school hallways.

“Our educators are overwhelmingly not comfortable returning to schools,” said Tina Williams, president of the Fairfax County Federation of Teachers. “They fear for their lives, the lives of their students and the lives of their families.”

In response to the groups’ statement, school spokeswoman Lucy Caldwell said the school system is sticking to its July 10 deadline and noted that teacher associations participated in the back-to-school planning process. She wrote in an email that the superintendent’s plan provides teachers and families with a choice, as many had requested in recent weeks via school-commissioned surveys.

She said the “health and safety of all staff and students” remains the administrators’ primary concern.

“Scheduling in a NORMAL year is a complex task,” Caldwell wrote. “This hybrid plan will be even more complex. Flexibility and patience will be required by all of us.”

Kimberly Adams, president of the Fairfax Education Association, said her organization’s view is that no teacher should return to work until a vaccine or treatment for the coronavirus becomes widely available. She said all school staff members must be allowed to teach virtually for as long as they feel is necessary.

And Becca Ferrick, president of the Association of Fairfax Professional Educators, took particular issue with the July 10 deadline, which she called “arbitrary” and “absolutely unacceptable.” The superintendent’s brief email, she said, offered almost no details about how in-person and virtual learning would take place, nor how those offerings would compare.

She has begun preparing a long list of questions for administrators. Among them: Will teachers working virtually and at school be required to teach the same curriculum, at the same pace? How will teachers’ possible medical conditions be factored into their application to work full-time from home, if at all?

“Asking our employees to make such an uninformed decision is akin to asking them to sign a blank check,” Ferrick said. “We will not do that.”