Loughton School is the fifth known school in Milton Keynes to have confirmed that a pupil has tested positive for COVID-19.
This comes as official figures show the coronavirus transmission rate, known as the R number, could currently be as high as 1.4 in the UK.
Sky News reports that ministers are currently considering another nationwide lockdown, with COVID-19 hospital admissions "doubling every seven to eight days".
The Office for National Statistics also says that there is "clear evidence of an increase in the number of people testing positive for Covid-19 aged two to 11 years".
And now MKFM can reveal that at least five schools in the Borough of Milton Keynes have confirmed cases of coronavirus.
Loughton School sent an email to parents on Wednesday (16/9) informing them that a Year 6 pupil tested positive.
It reads: "With the safety and well-being of all a priority, we are instructing pupils and staff within the class and any classes linked to this bubble in any way not to attend school and to self-isolate for a specific period of time as calculated by Public Health England (PHE)."
Students in certain classes are now self-isolating and can return to school at the end of the month. The school says these children will continue to be educated, but remotely.
The email continues to state that all other pupils must continue to attend school in line with PHE guidance, adding: "Based upon what we know and our segregation of year group ‘bubbles’, other year group pupils are highly unlikely to have come into close contact with the identified year 6 pupil."
The other schools confirmed to be affected by covid are Long Meadow School (six cases), Shenley Brook End School (one case), Stantonbury International School (three cases), and Ousedale School (two cases).
MKFM contacted Loughton School who refused to comment.