Pupils in Year 10, at E-Act Academy in Willenhall, have been sent home until Wednesday, December 2.
The school, on Furzebank Way, has remained open to other students.
A spokesman for the school said: "After careful consideration, we have asked our Year 10 cohort to continue their learning from home this week having been informed of cases of Covid-19 within the year group.
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"Our Year 10 students will return to the academy on December 2, and we remain open to all other year groups.
"This is a precautionary measure to ensure the safety and wellbeing of all our students and staff.
"We have plans in place which mean that our students can continue their learning without disruption from home, with daily contact from their teachers and access to a number of lessons.
"In the meantime, we continue to take every precaution here at the academy, including regular and focussed cleaning, good ventilation and strict adherence to social distancing, all of which have recently received positive feedback from the government’s Health and Safety Executive."