Nearly one-quarter of the city’s high schoolers walked out of classes Tuesday to bring attention to the impact of sexual assault and harassment on students, despite a similar walkout being held more than five years earlier leading to an “action plan” that got enthusiastic support in 2017.

All grades will be fully remote in reopened Cambridge Public Schools until Oct. 13, superintendent Kenneth Salim said Wednesday. “We can’t meet the requirements to keep people safe,” he said, according to people familiar with the conversation.

The Cambridge Education Association sent an open letter signed with hundreds of names to the School Committee demanding that the academic year begin with remote-only classes.

All nonessential public meetings are canceled effective Friday through April 30, Mayor Sumbul Siddiqui and City Manager Louis A. DePasquale announced Thursday, and public schools will close for two weeks.

What’s new with the coronavirus? Cambridge city and school officials were largely business as usual even as institutions around them and the city took dramatic steps against the spread of infection, including universities, winter markets, the Cambridge Housing Authority and many cultural events.

Cambridge Rindge and Latin School history teacher Kevin Dua is no longer listed in an online staff directory, and it is unclear if he remains an employee at the high school.

The School Committee rejected a report on the use of the “N-word” during a high school classroom discussion in January, but only after well over three hours of public comment in which black students said repeatedly that they didn’t feel safe at school.