Young kids love knock, knock jokes and the ones they tell often don't make sense but they will laugh their heads off anyway. When I started reading this book to my grandson, he didn't get it (he is only three) but when I told the jokes to my grand-nephew who is five, he thought they were hilarious. He actually started telling some of them over and over to his parents. The illustrations are simple and colourful and that is what got the attention of my grandson. This is a great book to read to young children and a teacher could use it to get her students thinking up their own jokes. This will be a hit in primary classrooms. I can see many teachers pretending they lost this book as kids will want to read it over and over as well as tell the jokes over and over or try to change them and make up their own, which probably won't make sense. A cute idea. The publisher generously provided me with a copy of this book via Netgalley. ( )