Cell Phone + 12 year old = Expensive Bill

Today I got my cell phone bill. Strangely it was $100 more than it usually is. Since we have a plan that gives us more than enough minutes every month, I went in search of an explination. What I found was that my 12 year old had downloaded 50 or so "premium text messages" at $1.99 a piece. I didn't know such a thing even existed. I'm still not entirely sure what they are. What I do know is that after a pleasant call to customer service her phone is now blocked from receiving them. I also know that she's going to be babysitting for free for the forseable future.