The book Can I Tell You About Gender Diversity? was written by LGBT activist CJ Atkinson and explains what it means to be transgender and go through a medical transition to children as young as seven.
The story, which is published later this month, follows 12-year-old Kit, who was born a girl but felt unhappy. Kit starts to wear boys' clothes, uses the pronouns 'he' and 'him' and changes his name to Christopher. He starts to use hormone blockers that will stop him going through puberty as a girl, while the book also explains how surgery can help when transitioning.
However, despite being used in schools to help encourage gender diversity, it has received criticism that it will confuse young children unnecessarily.
Lord Tebbit, Former Chairman of the Conservative Party, said the book is 'damaging to children to introduce uncertainly into their minds'.
It was also criticised by Daily Mail columnist Sarah Vine, who said: 'Their target audience is children not even ready to choose their A-Level subjects, let alone challenge their own biology.'
Image: Jessica Kingsley Publishers
However, CJ has now given a new interview and denied claims that the book suggests children should stop using the terms 'boys' and 'girls'.
'I would not go to a seven-year-old and say, "You can't call yourself anything." That's not what I've written', CJ told The Guardian.
'If you identify as a girl, assigned female at birth, and you like the colour pink, you like wearing dresses and sparkly things, that's awesome. But if you are a boy who likes pink sparkly things that's also awesome.'
This comes after it was revealed that Childline has been receiving an average of eight calls a day about transgender issues and gender dsyphoria.
CJ explained: 'The world is changing. A book like this is needed. People want to help. They want to know. They want to have conversations but they don't know how.
'A lot of the time it is not being dealt with or talked about in schools.'