Looks like there might be jokes hidden in there somewhere then… take a look for the author's anecdotes, they're usually funny. By "funny" I mean an adult trying to be funny but failing catastrophically.
Haha yeah i know i used cgp guides for my gcses and they had random jokes at the bottom if the page. But the books i have are student guides so i think thats why it doesnt have any (apart from above the barcode).