St Paul's Catholic School, in Leadenhall, said it has closed half of its Year 10, Year 9 and learning support bubbles until Monday, November 30.
Headteacher Jo-Anne Hoarty said: "This is a preventative measure to protect children and staff and represents a small percentage of the school population. We have been in regular contact with Public Health England, which is happy with our robust health and safety measures and our track and trace procedures.
"St. Paul’s continues to do everything possible to keep our community safe. We pray for the swift recovery of the pupils and staff who have tested positive. They remain in our thoughts and prayers."
The head said that remote learning is being provided for pupils who are self-isolating, and teachers will be monitoring their work and available for advice and feedback. And, if needed, the school said it will provide devices and free school meal packages.
Milton Keynes Council confirmed that 17 pupils and 12 staff tested positive, and 464 pupils are currently isolating.
The government's guidance around Covid-19 in schools says that an outbreak can be defined if a school has 'two or more confirmed cases within 14 days'.
If your child's school has had a confirmed case of coronavirus feel free to email [email protected] - we will publish the details, while you can remain anonymous.