A Newcastle head teacher signalled support for a circuit breaker lockdown as classes were closed due to the impact of coronavirus.
Students in years 7, 9, 10 and 12 at Excelsior Academy, in Scotswood, Newcastle, were told to work from home after a "large number of staff" were lost to "Covid-related absence".
In a letter to parents, principal James Andriot said: " Over the last week we have steadily lost a large number of teaching and support staff to Covid-related absence. Currently, approximately 30% of teachers and 50% of pastoral staff are absent in the secondary phase of the academy.
"We hit this tipping point over the weekend and at the start of this week. Firstly, the Year 8 bubble moved to online learning from Monday morning and we now need to send Years 7, 9, 10 and 12 home from Tuesday until the half-term break in order to run a smaller scale provision for Year 11 and Year 13."
Students at the school's Rainbird Primary would continue to be taught face-to-face, while Year 11 would have an earlier finish time.
The principal added: "I am saddened that we have not quite made it to the break without this course of action but we have to ensure that the pupils are safely managed in school.
"I was hoping that the government might impose a two-week circuit-breaker style lockdown linked to the half-term holiday as it would have helped the academy considerably but it does not seem that this will be announced for the North East.
"The media are currently reporting that Newcastle has the fourth highest number of cases in the UK (behind Knowsley, Manchester and Liverpool) so what we have seen in the local and school community appears to reflect the national picture."
In September, it emerged that a total of 64 students and staff were self isolating at the school after six people tested positive for the virus.
In the letter, Mr Andriot said there had since been "some additional cases" in the sixth form, Year 8, Year 11, and the primary school.
He highlighted additional cleaning and protection measures in the school, but urged parents to make sure they were following guidance, after some pupils attended school with symptoms.
He said: "We are still experiencing some parents/carers sending their children in to school with one or more of the three recognised symptoms (new, persistent cough / temperature of 37.8 degrees Celsius or more / loss of taste and/or smell). I appreciate that this is not always an easy decision to make, however, if your child has one or more of these three specific symptoms, you must keep them at home and get them tested as a matter or urgency and the whole household should isolate until you receive the test result."
This weekend, North East teachers in the National Education Union added their voices to calls for a "circuit breaker" lockdown, saying many schools were currently seeing "exponential" spread of the virus.