By Crockett Johnson
A small boy draws one line in the dark, and the line turns into the whole world he then has to find his way home from.
Harold wants a walk in the moonlight, so he draws a moon. Then a path to walk on, because he needs somewhere to put his feet. Nothing happens to Harold in this book — he makes it happen, one purple line at a time, and it is never explained to anyone. He draws an apple tree, then a dragon to guard the apples, and his own dragon frightens him so badly that his hand shakes, and the shaking line becomes an ocean, and he falls in. So he draws a boat. That's the pattern the whole way through: whatever goes wrong, the crayon is the way out. Then he gets lost, because he cannot remember where his bedroom window was, and the last pages are a boy drawing window after window in the dark, trying to get back.
For a child who is already drawing on everything in the house, this book says the thing out loud: the line you make is a place you can walk into. It teaches no technique at all. There is no step to copy, and Harold's own drawings are thin and wobbly and look like they were made by a four-year-old — which is the entire point, because your child looks at that dragon and thinks, I could do that dragon. Sixty-odd pages, most of them white, one purple line. It has been working since 1955 and it costs a crayon.