There are now 40 confirmed cases of coronavirus linked to Kingspark School, in Dundee.
The new number is an increase of four from late last week.
Three pupils and 23 members of staff have tested positive for Covid-19. The other 14 cases are through community contacts.
The school remains closed and all staff and pupils have been told to continue self-isolating.
There has been no change in the number of cases at St Johns Academy, St Clements Primary School, Grove Academy and St Peter and Paul Primary School.
The Happy Times out-of-school club at Downfield Primary has also had no change in cases.
Dr Ellie Hothersall, chairwoman of NHS Tayside’s incident management team, said: “It is reassuring that there has only been a very small increase in cases linked to one school over the weekend.
“I would like to thank all pupils, staff and identified close contacts who are currently self-isolating, which is vital to prevent further transmission of the virus.”
