Platt writes candidly about trying to function in a world that's not set up for the way her brain works.
She has come to appreciate there's nothing wrong with her dyslexic-shaped brain - it's just different. She believes we have all got wings and can all fly, but we need to be careful we don't clip young people's wings so much they are never going to fly.
A Christian, she was praying about the book when a picture of little wings came into her head. The book is subtitled The inside story: how to help dyslexics fly.
While there are a lot of books on dyslexia from an educational point of view, they don't give the whole picture by looking inside the head of a dyslexic, she says.
The teacher who smacked her or the principal who said she needed to try harder might have started a voice in her head that she would end up on the scrapheap of society, but she has realised she gives that voice power and she can change it.
Platt is in her mid-50s and doesn't think she could have written the book until now, when she can step back and see a much bigger perspective.
Dyslexics tend to be bright so parents and teachers expect them to do better than they can. They don't fit the profile of someone you would expect to find reading and writing hard, she says.
One of the key messages of the book is giving teachers permission they don't have to push students struggling with literacy and put increasingly difficult material in front of them before they are ready. Children with dyslexia or late learners need to work at their own pace. "It's not rocket science."
We wouldn't pluck a child who can't float from the shallow pool and put them in the deep end just because the rest of the class has moved on and can swim.
She writes of the need to respond to the content of a child's writing rather than react negatively to the creative spelling. "I'd want to know what she was really saying and give value to that."
Platt says she has got a great memory for stories, but not the random sequences so much of English spelling is made up of - she can quote Shakespeare, scripture, and poetry.
It wasn't until her first year at teachers' college that she discovered it wasn't normal for text to move when reading and that others were hearing sounds she couldn't pick up.
Careful consideration went into choosing a font and point size that is easier to read for the self-published book, and the text is printed on a cream rather than white background. Black text on white paper moves so much more, she says.
People with dyslexic brains are trying to move through a world set up for the 90 per cent who are not dyslexic.
For all the challenges she's faced, Platt realises she did get quite a good deal. "I've actually been very blessed. I've had challenges, but now I look back on my journey and haven't done too badly given the challenges I had."
Not everyone has a mother who will fight for them, some great teachers or a supportive experience being in youth groups. This combination gave her the confidence to go to Palmerston North Teachers' College and she went on to have an enjoyable teaching career before starting a family. The book is dedicated to her mother, Lesley Bardsley, who died in March.
"It's nice to look back on our life and realise how many heroes we've had in our life."
Platt and her husband Steve, a technical consultant, have two sons and a daughter, with a granddaughter on the way.
Platt listens to audiobooks while painting and plans to make On Being Dyslexic into an audiobook.
• The book can be bought from sarahplatt.co.nz/book.