Daniel Willingham, professor of psychology at the University of Virginia, says:
“The largest part of what makes a book enjoyable is pretty difficult to pin down. Different books are going to appeal to different children depending on their background and their preferences.
“Psychologists know only a little bit about what makes good writing and a good narrative – there are few generalisations that can be made. You can, to some extent, analyse prose regarding how comprehensible it is likely to be. But it’s theory driven: it’s to do with how words and phrases come together into what we might call idea units and how those idea units are referred back to.
“For example, if I mentioned something about Harry at the beginning of a paragraph and then I refer back to that detail later on, the number of ideas that intervened between those two mentions give us some idea of the comprehensibility of the text. And even that is an inexact science, figuring out what the idea units are.
“That’s certainly not the only factor that determines whether a text is enjoyable to read. But that’s the kind of thing that psychologists can point to as being relevant for whether a text is pleasurable to read.
“Another thing that teachers will be familiar with is the idea of a reading level, where you’re thinking about the rarity of vocabulary, the complexity of sentence structure and that sort of thing. The major problem with those sorts of analyses is that they’re very much content-free. You’re looking at the word frequency as a measure of the difficulty of the words, without considering what the words are. Part of comprehension is children’s ability to put ideas together. That’s one of the challenges of coming up with these numeric ratings of text difficulty.
“One of the things that I am frequently pointing out when I talk to teachers is that there are few things we know that we feel confident about: what makes a book enjoyable to read is something we still really don’t know about.
“It’s teacher experience that is going to be the trump card, here. Teachers who understand individual children in their class and also have a comprehensive knowledge of children’s literature at the right age and know how to make those matches.”