Little Johnny was doing OK at school, except for his maths. He couldn't be bothered, and just took it as a big joke, and a class where he could just goof-off.
His parents were desperate - how would little Johnny be an accountant if he didn't do maths (his parents weren't very ambitious for him, and more than a little boring - anyway, I digress). In desperation, they hired a tutor. But Johnny just spent all his time trying to look down her blouse. So they sent him to a military school, where he spent most of his time peeling potatoes, 'cause again he wasn't interested in maths.
In a last-ditch effort, Johnny's parents decided to send him to a Catholic school. Well, the effect was instantaneous. The first thing he did when he got home from his first day was go straight to his room, take out his maths book, and start studying. This went on for a few weeks, and Johnny's parents were beaming with pride, but they didn't know what had brought about this miraculous transformation.
One day, his mother decided to ask him why he was suddendly interested in maths.
"Well," said Johnny, "When I saw that they had nailed that dude to the big plus sign, I KNEW they were serious!"