Millions of parents have been forced to take time off work or arrange emergency childcare today because of school closures caused by a teachers' strike.
Many sympathise with the action; others are irritated by the inconvenience – and many of us don't even know why the strike is taking place.
Here we explain the causes and aims of today's teachers' strike - the biggest walk-out since the coalition government came to power.
Who's taking part in the one-day strike?
Members of the National Union of Teachers (NUT) at state schools and sixth form colleges in England and Wales are joining council and health workers, firefighters and civil servants – more than a million in total - across England and Wales.
Why are NUT members striking?
Teachers have a beef with the Government over changes to pay, pensions and working conditions.
What's the problem with pay?
Pension contribution increases and pay restraint mean that, since the coalition Government came to power, teachers' will have seen a 15 per cent fall in the value of their take home pay, according to the NUT.
Despite two years of pay freezes and a 1 per cent cap in 2013, a 1 per cent pay rise is now being imposed for 2014.
The union also says the fact that the Government is ending the national pay structure will make it harder for teachers to progress in terms of salary. Instead, pay will be based on performance – or performance related pay (PRP) from September. Concerns include the difficulty in measuring quality teaching, and the potential difficulty the scheme could bring in recruiting new teachers to the profession.
And what about pensions?
According to the NUT, pensions are one of the 'central parts of the campaign'. Issues include, pension contribution increases and a retirement age of 68.
What is teachers' beef about their workload?
The NUT argues that the on 'bureaucratic requirements' have led many teachers to believe they're not given the opportunity to dedicate enough time to teaching pupils in the classroom -= and has led to them working for 60 hours a week.
One NUT member said: "I'm striking because pupils deserve our time to be spent on their learning, not on form filling and bureaucracy."
The union also wants the Government to reduce the number of Ofsted inspections in order to give teachers more time to focus on their lessons.
What do striking demonstrators hope to achieve?
In a nutshell: dialogue. The NUT wants to see a more productive dialogue between the government, claiming talks are currently 'about implementation' rather than the policies themselves.
The union explains on its website: "In countries with productive dialogue with teacher unions, such as Finland, positive results flow for children, education and teachers."
Christine Blower, general secretary of the NUT, said that Education Secretary Michael Gove's constant reforms to the curriculum and examinations system are causing 'unnecessary stress to teachers, pupils and parents'.
What's the Government's reaction to the strike?
The coalition is sticking to its policy of holding down public sector pay and of privatising services. Ministers have criticised teachers for disrupting children's education.
Prime Minister David Cameron has also pledged to bring forward suggested changes to employment law so a certain number of people have to take part in a ballot for industrial action to be lawful. Business leaders and leading Conservatives have been pressing for a threshold of 50 per cent.
More on Parentdish: Why I am leaving teaching, Michael Gove
Video: In their own words - teachers explain why they're striking today