Thousands of kids have had an extra day off school because of teachers striking in England and Wales.
Loads of teachers refused to give lessons because they're unhappy with their pay and want more money.
Around 8,000 schools were affected, meaning some lessons were cancelled while other schools had to shut down completely for the day.
The strike also caused a headache for many mums and dads as they had to sort out special childcare.
Billie, Leonie and Jacob chat to Helen
There hasn't been a teachers' strike like this for 21 years.
At one big rally in London, some kids told Newsround's Helen why they were supporting the teachers.
Leonie said: "We think that teachers aren't getting paid enough so we're trying to protest to make them get more."
Her friend Jacob added: "Everybody's just trying to get our teachers paid more."
The teachers who went on strike belong to the National Union of Teachers.
A union is a group of people who have similar jobs and work together to look after their well-being at work.
Schools in Scotland and Northern Ireland weren't affected because teachers there have different pay packages.
The British government - which pays the teachers - has said it's not going to give in to their demands.