Pupils at Falkirk High School have been told to study at home for the next week after an outbreak of the Indian variant.
Staff and pupils will be tested for Covid at a mobile unit.
BBC Scotland understands up to 160 pupils are self-isolating. The school confirmed it would move to remote learning until 11 June as a precaution.
In the meantime pupils, staff and their families are being urged to undergo PCR testing to identify further cases.
The unit will be based in the school car park from Friday until Tuesday.
Falkirk Council said it would be open between 10:00 and 17:00 and no appointment was necessary. However, pupils under 16 must be accompanied by an adult.
Those sharing a household with pupils and staff are being encouraged to get tested at a separate unit located at Abbotsford House, David’s Loan, Bainsford.
Tests at this location should be booked via NHS Inform or by calling 0300 303 2713.
The council confirmed staff and pupils were among the positive cases but it did not give a number.
The decision to move to remote learning and carry out enhanced testing was made following talks between officials, NHS Forth Valley, Public Health Scotland and the Scottish government in a bid to prevent the further spread of the variant, which is now the dominant strain in the UK.
The council confirmed that almost all senior pupils had completed their SQA assessments but there were still a small number self-isolating, and the school was making plans to support them.
‘This is really important’
Cllr Cecil Meiklejohn, leader of Falkirk Council said: “We’re putting in the mobile testing unit to ensure that both staff and pupils can get results quickly.
“The decision has also been made to move Falkirk High to remote learning was not taken lightly however we recognise the concerns of pupils, parents and staff.
“Testing remains an important part of preventing the Covid-19 virus from spreading. We would encourage everyone connected with the school to get a PCR test as soon as possible.”
Dr Henry Prempeh, public health consultant at NHS Forth Valley, said: “Taking action now will help prevent further spread of Covid-19 which is why we are asking all pupils and staff, along with members of their households to get tested over the next few days.
“This is really important to help us identify any additional positive cases as many people with Covid-19 do not have any symptoms.”
