Open your child’s textbook to any page and look at it the way you’d look at a room — without reading, just seeing. Most pages are a wall: paragraph after paragraph, maybe a photograph placed like a decoration, a box with more words in it. Now think about the best explanation you ever received in person. Almost certainly, somewhere in it, somebody drew something.
That instinct — reaching for a pen mid-explanation — isn’t a flourish. It’s a confession that words alone are a narrow pipe. Text delivers meaning one word at a time, in order, and asks the child to assemble the picture in their head while also holding the sentence. A good diagram hands over the assembled picture whole: what connects to what, what comes before what, what’s big and what’s small — visible in a glance, checkable in a glance.
Checkable is the underrated part. When a process is drawn — this arrow feeds that stage, this splits into those — a child can interrogate their own understanding against it: do I see why that arrow goes there? A paragraph offers no such mirror. You can read a paragraph, nod, and have understood nothing, and neither you nor the paragraph will know. It’s the same trap as rereading: prose is smooth, and smooth hides gaps.
So we hold our pages to a test that sounds simple and turns out to be ruthless: does this picture show something, or does it just sit beside the words? A photograph of a farmer next to a chapter on farming shows nothing — remove it and no meaning is lost; it’s furniture. A diagram of how water moves from field to cloud and back is the meaning — remove it and the chapter gets harder. Furniture makes a page prettier. A real figure makes a page teachable. Books are full of the first kind because the first kind is easy.
When we build a chapter, the visuals aren’t added after the writing, the way photos get dropped into a finished layout. We start by asking which ideas in this chapter are spatial, sequential, or comparative at heart — most are — and those get drawn, not described. The words then do what words are genuinely best at: the why, the story, the voice. A page where everything is prose is, to us, a teacher lecturing with the blackboard switched off — the lesson might survive it, but why should it have to?
There’s a fair objection: plenty of “visual” books are gimmicks, all bubbles and mascots and nothing underneath. Agreed — decoration isn’t the goal, and neither is entertainment. The test cuts both ways: a cartoon that shows nothing fails it exactly the way a stock photo does. What earns a place on our page is meaning made visible — nothing less, nothing else.
Next time you evaluate a book for your child, try the room-glance test before reading a word: cover the paragraphs and ask what the page still teaches. A good page keeps teaching with the words hidden — because someone did the hard work of drawing the thinking, not just typing it.