Secondary schools and colleges across the region are facing last minute planning after being told pupils' return to classes in January will be staggered.
Exam-year students will go back to school as normal after the Christmas holidays, but the majority of secondary school pupils will start the term learning online from home.
Primary school children will go back to class as normal on January 4, alongside students in exam years, vulnerable pupils, those in special schools, and key workers' children, the Department for Education (DfE) said.
But most secondary schools and colleges will see a full-time remote education during the first week of term with the aim of face-to-face education for all students resuming on January 11.
It is hoped the staggered return will allow headteachers to roll out mass testing of children and staff in the new year.
But education unions are concerned about the logistics of setting up a mass testing programme and they have criticised the government for making a last-minute announcement just two days before the end of term.
Scott Lyon, Norfolk joint division secretary for the National Education Union (NEU), said the Government's announcement was “shambolic”.
He said: “School leaders across Norfolk have put amazing measures in place to try to protect staff, children and communities as much as possible but at the same time there is only so much they can do.
"Now before Christmas it feels like impetus has been put back on schools but with two days to go.
“We are going to have to filter pupils’ return but working with the assumption that there will have been some massive social mixing in the previous two and half weeks.”
Schools and colleges will be able to offer returning students two rapid tests three days apart in the first week of term as part of the rollout of testing.
Testing will be optional but strongly encouraged, particularly in areas of higher prevalence of the virus. Consent will be required from the student or parent.
The DfE has said guidance will be provided to schools and colleges shortly on how to set up and staff the testing sites.
Education secretary Gavin Williamson said: "This targeted testing round will clamp down on the virus as students return from the Christmas break and help stop the spread of Covid-19 in the wider community.
"Building on the fantastic actions that schools and colleges have already taken to be as safe as possible, this additional testing will catch those who have the virus but are not showing symptoms to help schools and colleges stay in control of the virus throughout the spring term."
Mr Lyons said: “Norfolk has been coy about testing but any sane person will say that is absolutely impossible in schools especially with the short notice given and with no additional money or supplies or staff training.
“To try to establish that from January is just too much. They are telling headteachers they have the responsibility of taking staff away from the frontline learning to do testing with no details about training or resources.”
Geoff Barton, leader of the ASCL head teachers’ union, and a former head in Bury St Edmunds in Suffolk, said: "We are very concerned about the feasibility of setting up a testing programme at the scale envisaged.
"We welcome the limited support we understand will be available, but this is a huge exercise requiring processes to be established and communicated, parental permission to be obtained, and doubtless innumerable other logistical issues to be overcome."
Positive cases and staff self-isolating has still had a significant impact on Norfolk schools with 13 either closed or partially closed and dozens more affected this week.
Secondary school pupils have among the highest infection rates, but early findings from a study suggest that the proportion of pupils and teachers with Covid-19 mirrors the proportion in the local community.
The survey also found that 27.6pc of schools had one current infection, 27.6pc had between two and five, and 44.8pc had none.
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