Normally, Britney Spears can't wipe her ass without a group of paparazzi snapping pictures of it, but somehow this story didn't sneak out until today:

Britney Spears is no stranger to odd antics, but her behavior on January 7th was particularly bizarre.

A source tells usmagazine.com the "scantily clad" pop star showed up at a Beverly Hills elementary school, saying she was there to pick up someone else's kids.

The singer parked her car outside the school just before 4 p.m. and spent 10 minutes smoking cigarettes and talking to herself while she waited for classes to let out.

"She was just rambling and confused," says the witness who approached her to ask if she was OK. "She said, I'm here to pick up my kids." But then she changed her story and said, 'They aren't my kids; I have a new attorney and I came to pick them up for her.'"

Before driving off (without any children), she chatted up the female witness: "She said, 'You're so nice. You should give me your number. I don't have very many friends.'"

Okay, we all know Britney is crazy, but to get proper perspective, let's put her against some of the more famous crazy people of our time: