Children were isolating due to Covid-19 less than a fortnight after P1 to P3 classes returned to school.
Primary schools in Fife and Angus have asked families to keep children at home due to coronavirus cases.
Strathmore Primary School, in Forfar, had two cases of the virus linked with it. A number of children remain at home isolating.
Dunnikier Primary School, in Kirkcaldy, has also been affected.
Cases detected last week
It is understood the cases were all identified last week, the second week of younger pupils being back at school.
Both schools are preparing for the return of the rest of their pupils in P4 to P7 on Monday.
A spokesman for Angus Council confirmed that two cases had been linked to Strathmore Primary School, in St James Road.
She said: “As a result we have asked some pupils to isolate.”
NHS Fife revealed that at least one Covid case had emerged in a either a pupil or staff member at Dunnikier Primary School, in Balsusney Road, sometime between March 1 and 7.
Families of some children have been asked to keep them at home to isolate.
It was not stated whether these were pupils who had recently returned to the school or had been attending since the start of the term.
Schools have been open since the end of the Christmas holidays to children of key workers and vulnerable children.
We've published the latest weekly schools and nurseries COVID-19 update on our website, here:-
The update covers the period from Monday 01 March to Sunday 07 March 2021. pic.twitter.com/7I7xm83cXu
— NHS Fife (@nhsfife) March 9, 2021
NHS Fife has begun issuing weekly information on Covid-19 cases connected to nurseries and schools and Dunnikier was the first school reported since younger pupils returned to school on February 22.
It said cases will be reported where five or more school contacts have been required to isolate following contact tracing.
Scotland-wide 466 children aged between five and 17 tested positive for Covid-19 last week, bringing the total since the start of the outbreak to 15,172.
NHS Fife reminded anyone with Covid symptoms to self-isolate immediately and order a test from NHS Inform.