How to keep an idiot busy for 30 seconds?

Another fun one: ask them to count how many times the letter F appears in a paragraph full of “of”s. Most people miss half of them and keep re-checking again and again.

Classic one 😅. Just tell them: “Read the back of this paper to see the instructions” and then write “Please read the front” on the back. They’ll keep flipping it for a while. Works like a charm.