Moseley Park Academy sent a letter to parents on Tuesday about the coronavirus case.
The letter says: "We have been advised by Public Health England that there has been a confirmed case of Covid-19 within school.
"The Year 8 student is now self-isolating with family for a 14 day period. We have followed national guidance and have identified that your child, as part of the Year 8 bubble in school, may have had close contact with the affected child.
More Covid-19 coverage:
"We recommend that your child now stays at home from 21st September and return to school on the 5th October, providing they are not demonstrating any symptoms.
"During this period of self-isolation, all Year 8 students access their lessons via MS TEAMS. These lessons will be ‘live’ at in line with their normal timetable.
"We are asking you do this to further reduce the spread of Covid 19 to others within the community.
"Other members of your household can continue normal activities, providing your child does not develop any symptoms within the isolation period. In this case the family will need to self -isolate for a further 14 days from the point at which symptoms were displayed."