I have been a "technical document" writer for a very long time and a few years ago decided to write a book for each of my daughters as a birthday present. I was surprised at how much I enjoyed writing them and was asked to write a few other bespoke books for birthdays for other people. As my younger daughter was struggling to read, I wrote her a book using the top 100 primary school words on a topic I knew she would enjoy. I did this in order to help her catch up with her class as she showed little interest in reading most books. After later discovering that she was in fact dyslexic (and shortly after that I was as well). I decided to write a series of books specifically aimed to help struggling readers which would use a friendly font along with lots of pictures and puzzles to help keep the reader interested in reading.
My books have been used by a couple of teachers in class, and the feedback so far has been very positive. I was inspired to use this style of "adventure book" after attending a lecture at the Edinburgh book festival where they talked about the improvement this style of book can have on less avid readers as it's less intimidating than a more traditional style of book which can seem quite daunting when looking at page 1 of 200 pages!
