All San Bernardino County public schools will be closed beginning Tuesday, March 17, to help prevent the spread of the novel coronavirus.

San Bernardino County reported its first confirmed case of the virus, COVID-19, on Sunday in Fontana. Though there had been no countywide demand Friday to shutter all schools, public instruction officials began announcing closures. By midday Friday, about half of the county’s school districts had announced closures.

Many area superintendents said they didn’t want to take unnecessary chances.

“We are all in uncharted waters as we work together to prevent the spread of the illness, and it has become clear that the appropriate path is to close schools to protect staff and students,” Chaffey Joint Union High School District Superintendent Mat Holton wrote in a letter posted to the district’s website Friday.

Redlands Unified, which began its two-week spring break recess Friday, on Saturday announced it would close campuses for an additional week. Students are now scheduled to return Monday, April 6. Other school districts closed over the weekend as well. Closure dates vary by district, with several beginning their spring breaks early or extending that recess.

Trona Joint Unified School District was the last district to announce a closure after a board meeting Monday morning, March 16, to discuss its response to the coronavirus.

Here’s how long schools across the county will be closed:

The following Inland Valley school districts are covered by the Los Angeles County order to close all schools for two weeks beginning Monday, March 16. Some have longer closures due to planned spring break recesses:

Bonita Unified: March 16 through April 3

Claremont Unified: March 16 through April 10

Pomona Unified: March 16 through April 3

Walnut Valley Unified: March 16 through April 17

Not all school functions are shutting down, though.

The Chino Valley Unified School District’s plan “includes seamless continuation of educational instruction; steps for cleaning, disinfecting and restoration of schools and facilities if needed; and preservation of critical school district services,” Superintendent Norm Enfield wrote in an email to parents and staff.

Families will receive instructions on how to get lesson plans to continue learning at home, he wrote.

Similarly, San Bernardino City Unified and Ontario-Montclair teachers are preparing ways to teach students remotely and the district plans to provide meals for students during the period. More than 88% of San Bernardino City and 81% of Ontario-Montclair students receive free or reduced-cost meals, according to the California Department of Education.

Chaffey students were sent home Friday with updated teacher contact information, instructions on how they will stay in touch during the shutdown and “flexible instruction plans.”

“While our campus facilities are closed, students are expected to continue their classwork as detailed in the information that is being communicated by each of their teachers,” Chaffey Superintendent Mat Holton’s letter reads.

In a statement late Friday, San Bernardino County Superintendent Ted Alejandre said he supported the decisions made by local school districts.

“The coronavirus has caused great anxiety and uncertainty in our schools and communities,” he said. “The safety of our students and staff remains our top priority, and we are confident this is the best course of action to take for the 406,000 students who attend public schools in San Bernardino County. I support our districts in their efforts.”

Staff writers Jessica Keating and Javier Rojas contributed to this story.

This story may be updated as additional information becomes available.

For more information about what Riverside County school districts are doing, click here.