The Earls High School sent a letter to parents confirming the case.
It says: "Unfortunately we have just heard of a confirmed case of coronavirus in our school community and as a result there could be quite a number of contacts.
"As a precautionary measure, while we complete our contact tracing we will be sending students from Year 10 home today.
More Covid-19 coverage:
"We will then contact any parents by phone if their son or daughter needs to self-isolate and follow this with a letter.
"Once this is complete we will then make a decision on how school will be for next two weeks for Year 10 and I'll email again later this afternoon."