Today, hundreds of thousands of people took part in a day of protest against global climate change, many led by schoolchildren who were mounting a “school strike” to save the planet.

Gathered at Westminster, pupils and their families held placards and banners with environmental slogans, perhaps inspired to take part by 16-year-old Greta Thunberg’s activism.

This morning, schools minister Nick Gibb warned that missing school to join the strike could affect pupils’ exam grades, and the NAHT heads’ union has also suggested that pupils might be unsafe on the march.

In the crowds, however, some parents - and indeed teachers - had brought along their children or pupils to take part.

Teacher and mum Emma Alcaraz Laws said she attended the protest today, along with two friends and their children, because the strike was simply too important to miss.

“It’s really important children are aware of what’s going on with the planet, and if there is no planet, why be at school in the first place?” she said.

She added that it was the impact of learning about climate change at school that had made her children more passionate about environmentalism.

“Because of what they’re doing at school, our children come home and say, ‘Mummy, why is this wrapped in plastic, can’t we get something that isn’t wrapped in plastic, why can’t supermarkets sell things without all this extra packaging?’ They have made all of us more aware at home of what we should be doing.

“We’re making great changes at home, and hopefully the government will listen to this, too.”

She said that children needed to miss school to witness the protest, and see “the unity of everyone coming together to fight this battle”.

Her friends added that their children were far more aware of climate change than older generations, and saw little point in being at school when the future of the planet was at stake.

Music teacher George Papakyriacou had brought a group of pupils and their parents along to the protest.

“I think it’s so important to educate children to understand what’s going on around them - climate change is real, it’s happening, it’s going to affect our future. And they can make changes, because they’re the ones that really can and are willing - more than adults, to be honest,” he said.

He said he planned to start an environmental club at his school, and that missing school to join the protest was useful for pupils, as they were the generation who would face the “drastic” consequences of climate change.

Kevin Courtney, general secretary at the NEU teaching union, addressed the crowd, saying, “Today, we adults are the students, and you are the teachers.”

He said pupils should be “proud” of what they were doing in holding adults to account, and said they did not need to have the answers to global warming, but they were right to pose the questions.

“Never give up what you are doing today,” he said as he ended his speech to cheers from the crowd.

“I feel like it’s important to come today with my children, because it’s their future and usually they don’t have a say in these sorts of things - I think the amount of children that care is very telling,” said one parent, who attended the protest with her young daughter and school-age son.