Have Fox in Socks. That's a great tonguetwister book. Give it to a friend to read to your kid without pointing out the tonguetwister part--it says it right on the cover, but people tend not to notice. It starts out sounding like regular Seuss, but when you get to luke's duck liking to lick lakes and through three cheese trees three fleas flew while freezy breeze blew, it's pretty wonderfully awful. This was actually my favorite seuss book to read to my daughter, because gave me something to think about, moreso than Big A Little A What Begins with A Aunt Annie's Alligator A A A.

Oh Say Can You Say is worse, but the title sort of gives it away, so it's harder to play this joke.

(if you'd told me 10 years ago that I could write this sort of post, I would have laughed at you).