The three friends were walking home from school.
“What shall we do this afternoon?” said one.
“I know, “said the second, “let’s spin a coin. If it comes down heads let’s go skating, and if it comes down tails let’s go swimming. “
“And if it comes down on its edge, “said the third, “let’s stay in and do our homework!”
This joke is included in the Black Book of Jokes. You can order it from here.