Over 23,000 schools will be affected on Wednesday in the biggest day of industrial action for a decade – with many shutting alltogether.
It comes as members of the National Education Union (NEU) in England and Wales demand above-inflation pay rises.
Figures suggest that up to 150,000 teachers could be out on strike that day.
90 per cent of the NEU’s 300,000 members voted for Wednesday’s walkout, turnout was 53 per cent.
Most schools impacted will be completely shut as its unsafe for kids if a school is understaffed, The Times reports.
But others will be partially open for priority pupils, including vulnerable youngsters, exam-year pupils and kids of key workers.
Kevin Courtney, joint general secretary of the union, said leaders will meet Education Secretary Gillian Keegan in a “last chance” effort to avoid strike action on Monday.
A source close to Ms Keegan told the PA news agency she will use the meeting to reiterate her call from the weekend for teachers to inform schools if they plan to strike.
Check Wednesday’s full list of school closures here to see if your child is affected.
The action will be the first of seven days of strike chaos planned by furious NEU teachers in England and Wales throughout February and March.
On February 1 school staff in England and Wales will stage their first walkout.
Then, strikes will go ahead on a regional basis on February 14 and 28, and March 1, 2.
Finally, nationwide walkouts in England and Wales will take place on March 15 and 16.
Parents and guardians are entitled to time off if normal arrangements are broken, but it would be up to the employer if they would pay for this time off.
It is thought around 32,000 teachers have signed up to join the NEU since the strike was announced on January 16 – all new members are eligible to walk out.
Under current strike rules teachers have no obligation to let schools know are walking out.
Members of the NASUWT and NAHT teaching unions are not striking.
Walkout Wednesday will also see 500,000 other workers stay at home in scenes likened to a general strike.
Train drivers, civil servants, university lecturers, bus drivers and even security guards will all hang up their uniforms in rows over pay.