Some of the women reading it don't seem to fully appreciate the joke. They don't exaggerate the wide mouth and they don't change their tone for the ending. They deliver a deadpan reading. And that's not fun. I've seen it done with the gentleman reading the book using his fingers to stretch his mouth to voice the frog, then at the end uses his fingers to squeeze his lips tight and squeak out the voice for comedic contrast and that totally cracks up little kids.
This boy in the video wants to flip the pages back and forth to see the jaw and beak action. With this book, it is the exact same mechanism on each page applied for different animals, V mechanisms in opposition, different artwork painted on the mechanism and background, the most simple mechanisms possible, the first one people learn. Very little children like Jacob are startled by the sudden projections and they want to stick their fingers in and grab it.
The Australian dad kills me. He knows how to read the book. And he knows how to let his boy play with the book, "The wide-mouth frog was still eating flies when he sore a big great alligadah."
My nephew got his copy today. I'm very interested to know how it went over. I hope my brother reads it well as this dad does. I told this joke one time at lunch and he and his Navy diver friend cracked up laughing.