With a push from campaigners and some parent groups, more British schools are allowing pupils to explore their gender identities in a bid to be more inclusive and stop bullying.
Cumberland High School, a sprawling establishment with nearly 1,500 pupils in east London, is one of hundreds of schools around the country that is taking steps to break down the binary division between male and female.
Cumberland has adopted a more liberal uniform policy that blurs gender boundaries and is adapting its infrastructure -- such as gym changing rooms -- in an effort to be more accepting.
"Changing is an issue for some pupils so we have gender-neutral changing rooms that anyone can use," said Jake Jones, a sports teacher at the school who is also head of the personal, social and health education department.
"I think a lot of our inclusive approach comes down to terminology," Jones told AFP, pointing out that teachers are being encouraged to avoid "boys" and "girls" and use non-gendered terms such as "pupils" or "children".
At the Brindishe Schools in south London, pupils are taught about the possibility of using "Zie" as a gender-neutral option instead of "he" or "she".
Education and health administrators say they are finding that more children today are questioning their gender identity.
"When you make something more gender neutral... for those children it becomes less of a worry, less of a concern for them that they are different and they don't fit," said Charlotte Dougan, assistant headteacher at Brindishe Manor School.
"They can just be themselves," she said.
Lauren Campbell, deputy head at Brindishe Green School said: "It is never too young to start".
"I think it is very important that we educate the children the best we can from that very early starting point, in terms of teaching them about gender, about gender stereotypes," she said.
Not all British parents agree with this view.
The National Health Service this week was forced to remove a gender question from primary school questionnaires in Lancashire in northwest England after a wave of criticism from parents and lawmakers.
The question, on a survey aimed at children aged 10 and 11, asked them if they felt "the same inside" as the gender they were born with and offered three gender options "girl", "boy" or "other".
Whatever parents may feel, there is evidence of a growing number of children and young people grappling with gender identity issues.
The Gender Identity Development Service (GIDS), a health agency for youths in London and Leeds, said their consultations have risen from just 95 in 2010 to 2,016 so far this year.
"The question is does somebody need to know what your anatomy is to know who you are? Whose choice is it to define oneself?" said Sarah Davidson, consultant clinical psychologist at GIDS.
According to figures from Educate and Celebrate, an association that promotes education that is not gender binary, some 220 schools in Britain have adopted a single uniform for boys and girls.
"What some schools are not realising is that this is fundamental to a young person's life and identity," said Elly Barnes, founder of the association.
"If you cannot be who you are, if you are constantly told that you can't do that because you are this, you are not going to get the best out of a child."
For the past five years, this former music teacher and her team have trained thousands of teachers and developed best practices on inclusion aimed at fighting bullying in schools and promoting diversity.
It is a challenge, made more difficult by the legacy of Section 28 -- a piece of legislation that was approved in 1988 and remained in force until 2003.
The law forbade the teaching in state schools in Britain of "the acceptability of homosexuality as a pretended family relationship."
"It was a horrific peace of legislation that ruined the life of children and teachers and families, all over this country," Barnes said.
She said the "legacy" of the legislation was that teachers "still have terrible problems being able to talk about anything to do with gender identity or sexual orientation within the classroom, because they had the instinct that you just couldn't".
Laws have been overhauled since the time of Section 28, particularly following the adoption of the Equality Act in 2010 which banned any form of discrimination based on gender or sexual identity.
Even the Church of England has revised its position.
Last month the Church published a set of guidelines for its 4,700 schools that read: "Childhood needs to be a period where we can make mistakes, try things out, explore projects and identities".
"This should inform the language teachers use when they comment, praise or give instructions.
"It may be best to avoid labels and assumptions which deem children's behaviour irregular, abnormal or problematic just because it does not conform to gender stereotypes or today's play preferences."