There is "no good reason" for schools to remain closed after the summer break despite fears about swine flu, the Government has announced.
It comes as ministers warn that schools should take action if any pupils are bullied after suffering from the virus.
Health experts predict the number of flu cases to rise sharply in the autumn and winter months but evidence shows that closing schools is of "limited benefit".
Updated guidance from Education Secretary Ed Balls says schools should re-open as normal, with millions of children due to start class next week.
It comes as teachers are given access to a swine flu nursery rhyme to help teach youngsters the importance of good hygiene.
The "catch it, bin it, kill it" nursery rhyme is accompanied by posters of young boys and girls sneezing and a comic strip.
One of the lines in the nursery rhyme is: "Kill the germs they make us sick, come on everyone wash them off quick!"
When the flu outbreak began earlier in the year, some schools were closed as a precaution to help try and contain the virus.
But the UK has now seen too many cases of swine flu, meaning closing schools will have little effect.
In a message to teachers, Mr Balls said: "We have been closely monitoring the spread and severity of swine flu over the school holidays.
"The latest scientific advice to the Government is that individual school closures are now of limited benefit in stopping the spread of disease.
"Given the mildness of the virus, the expert medical advice is that there is no good reason for schools to remain closed after the summer holiday.
"We therefore expect all schools and early-years and childcare settings in England to reopen as planned at the beginning of the new term.
"However, it is still essential that adults or children with flu-like symptoms should stay away until they are free of those symptoms."
Schools should also take steps to ensure children who have had swine flu are not bullied on their return to class, the Department for Children, Schools and Families (DCFS) said.
In a Q&A for teachers, it said: "It is not acceptable for young people to be bullied as a result of them having swine flu or any other illness.
"If a young person is bullied for that reason, they or their parent can report this to any member of staff at the school.
"Schools are obliged to have a range of measures in place to prevent and tackle bullying.
"We would expect them to act swiftly and decisively to resolve the matter when bullying is reported to them as a result of a young person having swine flu."
It also said schools are well-equipped to tackle bullying by children from other schools.
"In particular, schools have the power under section 89 (5) of Education and Inspections Act 2006 to take measures to regulate the conduct of pupils off site.
"If the bullying taking place is of a serious or violent nature the schools involved may wish to work with local police or the LA community safety team as part of their response."
The number of deaths linked to swine flu in the UK now stands at 66 after a 52-year-old man died in Scotland on Wednesday night.
Seven people have died in Scotland, 57 in England, one in Wales and one in Northern Ireland.
Chief medical officer for England, Sir Liam Donaldson, said yesterday there were an estimated 5,000 new cases of swine flu in England in the last week.
The first vaccinations of people in at-risk groups - such as those with asthma and diabetes - are expected to take place in October after the vaccine receives its licence.