Its passable, but definitely PG-13

Three third graders, an Irish kid, an Italian kid and a Hillbilly kid are on the playground at recess. One of them suggests that they play a new game.

"Let's see who has the largest weenie," says the Irish kid.
"Okay." They all agree.  The Italian kid pulls down his zipper and whips it out.
"That's nothing," says the Irish kid.  He whips his out.  His is a couple of inches longer.
Not to be outdone, the Hillbilly kid whips his out. It is by far the biggest.  That night, eating dinner at home, the Hillbilly kid's mother asks him what he did at school today. "Oh, we worked on a science project, had a math test and read out loud from a new book and during recess, my friends and I played 'Let's see who has the largest weenie."

"What kind of game is that, honey?" asks the mother.
"Well, me, Anthony and Patrick each pulled out our weenies and I had the biggest!  The other kids say its because I'm a Hillbilly.  Is that true, Mom?"

Mom replies, "No, Honey. It's because you're twenty-three..."