Schools have made many changes to cope with coronavirus – from social distancing to altering the school day.
Many are also closing early for Christmas, to help reduce the number of infections.
London Mayor Sadiq Khan has asked the government to shut schools in the capital, and reopen them later in January. In the borough of Greenwich all schools are being asked to move to learning online from Tuesday.
Mass testing is being rolled out to secondary school staff, pupils and their families in parts of north east London, Essex and Kent with the highest coronavirus rates.
From January, schools in Wales can offer rapid testing to children who have had close contact with someone with coronavirus.
If someone tests positive, they must be sent home to self-isolate for 10 days.
The school must then contact their local public health protection team, who will advise on who else should be sent home.
Anyone who has been in close contact with the person testing positive must self-isolate.
The NHS says the main Covid-19 symptoms are:
If a child shows these symptoms, they – and other members of their household – should self-isolate for 10 days and get tested if possible.
A runny nose is more likely to be a symptom of a cold, and is not a reason to get tested for coronavirus, says NHS Scotland.
Measures include hand sanitiser stations, one-way systems and staggered break times.
Improved cleaning procedures have been introduced, and social distancing wherever possible.
In England, younger children are being encouraged to mix in small groups or “bubbles” as they are unlikely to stay 2m apart.
Older children, such as those in secondary schools, are being encouraged to avoid touching one another as much as possible.
Pupils and teachers in secondary schools and colleges in England and Wales must wear face masks in communal areas.
Scotland’s senior pupils (years S4-S6) and their teachers must also wear them in class in level 3 and 4 restriction areas.
In Wales, face coverings are recommended in high schools when social distancing is “unlikely to be maintained”.
In Northern Ireland, face coverings must be worn in the corridors of post-primary schools, and on school and public transport.
Scotland’s Higher and Advanced Higher exams have been cancelled for 2021, with final grades based on teacher assessment.
The National 5 exams have also been cancelled.
The Welsh government has cancelled next summer’s GCSE, AS and A-level exams, with grades based on classroom assessments.
In England, A-levels and GCSE exams are due to go ahead with reduced content for some subjects, and later exam dates.
In Northern Ireland, A-level, AS and GCSE exams will start a week later than usual.