It all started with a thread on Mumsnet a few years ago, when people were getting frustrated trying to find Christmas presents for their kids,” explains Olivia Dickinson, a London-based digital consultant. Faced with a wall of pink heels and Hoovers for girls or drab games and science toys aimed only at boys, parents on the forum decided they were going to push back against the lazy stereotyping that they felt was limiting their children.

By 2012, this sentiment had coalesced into a campaign group, Let Toys Be Toys, which used social media to persuade retailers to display their wares in broader, less gendered categories. It was phenomenally successful and five years later, the campaigners have turned their attention to schools.

Simplicity was the secret behind the group’s early victories, says Dickinson, who volunteers her time for Let Toys Be Toys and often acts as its public face. “We kept our ‘ask’ very simple,” she explains. “We’re challenging stereotypes in childhood so we just wanted to ask retailers to stop labelling things as ‘for boys’ or ‘for girls’. Why pigeonhole kids when they’ve got the whole world before them?”

Boots was the first shop to capitulate, followed by a number of major supermarkets. “Toys R Us was a big one,” Dickinson adds. But although it was a successful campaign, she says the group had a sense that there was more they needed to do. So in 2014, the team set their sights on books.

“The big offenders are often non-fiction or collections of stories,” explains Dickinson, pointing to the common trope of princess stories for girls and adventure or gross-out tales for boys - sugar and spice versus slugs and snails.

Pushing for change

It may seem harmless, but a 2016 study by researchers at Brigham Young University in the US found that “princess culture” (perpetuated by Disney in particular) reinforced limiting gender stereotypes.

The Let Books Be Books campaign launched on World Book Day 2014 and asked publishers to remove overt “boys” and “girls” labelling from their covers. So far, 10 children’s publishers have agreed and the team is keeping up the pressure on the rest.

Clearly, this group knows how to push for change, so schools had best be prepared: they are next on the agenda.

“Very early on we had the realisation that tackling retailers was all very well, and we were getting lots of parents involved,” Dickinson says. “But then children go to nursery and on to school, and they are still experiencing gender stereotypes in lots of different ways.”

This could be “gender policing” from peers, for example, a boy finding out he can’t play in the Wendy house, or boys telling a girl that robots aren’t for her. Then there’s more subtle messaging and language in the classroom, such as only using examples of male scientists, segregating toys and activities to different areas of the room, or allocating tasks by gender, such as boys stacking chairs and girls looking after class pets.

“We felt there was a need to do something in schools because we were hearing so many bad tales from parents about the way that their children were being treated by teachers, as well as their peers,” Dickinson says. She stresses that she’s not blaming teachers for unintentionally reinforcing stereotypes. She recognises that it takes thought, time and effort to spot and iron out the unconscious biases that exist in all of us.

“It’s such an effort to keep being aware of it, but it’s really important,” Dickinson says. “Our ingrained social assumptions are really strong even in children - for example, most GPs are women and kids are more likely to see a female GP, yet they still say men are doctors. Or their mum will be the only person in the family who drives, but they still say only men drive.”

Dickinson wants to encourage all teachers to regularly check themselves and their language - who did they ask to do which tasks today? Did they use pet names for the girls but not the boys? - and to think about the subliminal messages they are sending out (there is a list of 10 ways to challenge gender stereotypes in the classroom at bit.ly/10GenderChallenge).

The campaign team are also working to make the impact of gender stereotypes a more explicit part of the curriculum. Because the campaign was initially based on toys, they’ve used gendered toys as the basis for a lesson plan for key stage 2 (bit.ly/LTBTplans). Expanding this idea, the team has now developed a lesson plan for Year 9, which focuses on gendered language and sits within the English curriculum. There is also a lesson for early years and Reception children, and the campaign team are keen to hear further ideas from the teaching community.

Does Dickinson expect the campaign’s impact in schools to be similar to that already achieved in publishers and toy shops?

Gender stereotyping is a habit for society, she says, pointing out that we don’t use racist words or homophobic slurs that were commonplace just a few decades ago. In Sweden - often held up as a gender-neutral utopia - concerted school-wide efforts to tackle gendered language and activities since the 1990s seem to be making a difference.

More than ‘ker-pow’

And she hopes for broad support. We are becoming increasingly aware that placing limits on girls is a bad thing, discouraging them from pursuing Stem subjects or sports, for example. But Dickinson believes that the harm done to boys by stereotyping is equally worrying, reinforcing problems with exclusion, bad behaviour, and even increasing their suicide risk later in life.

“Actually, the boys are more limited by this than the girls,” she says. “There has been some progress in pushing back on the limitations of what girls ‘should’ like and do, but at the same time there hasn’t been the same expansion of what’s OK for boys.

“We’re setting boys and girls up to think of themselves quite differently, but it’s important for boys to be able to feel that they can do more than just go ‘ker-pow!’ and that they can be in touch with their feelings and talk properly.

“And for the girls, they need to feel that they can do anything and be given the opportunities to practice things such as construction or sports.”

Ultimately, the world is changing and our views of gender need to change, too. We live in a time where a growing number of world leaders are women, including the prime minister, but none of them are prancing round in a pink princess dress. The heads of the Metropolitan Police force and London Fire Brigade are female, yet virtually all firefighter or police dressing-up outfits are aimed at boys.

“The bigger picture that we’re starting to look at is why do we need this at all?” Dickinson argues. “If this was racism, or homophobia or disability discrimination, people would be appalled and say, ‘I would never do that!’ We need to get gender awareness embedded in teacher training and embed it at whole-school level to address unconscious biases and get equality of opportunity for girls and boys.”

Dr Kat Arney is a science author, broadcaster and co-presenter of the BBC Radio 5 Live Science show. She tweets @harpistkat