When Greg Christofferson of Cheyenne Wisconsin bought cellphones for his family from Verizon Wireless, he opted for a plan that excludes texting not knowing that choosing such an option meant paying for each and every text sent and received. So when the carrier called to discuss the monthly bill, Christofferson was stunned. His 13 year old daughter Dena had sent and received nearly 20,000 text messages for the month, which works out to about 700 a day. The bottom line? A bill of $4,756.25 that was followed by a call from Dina's principal telling her parents that the teenager was getting 5 "F's" on her report card. Mr. Christofferson happened to own a tool that he knew would prevent such a bill from coming again-his hammer. The phone was smashed to little bits and his daughter was grounded. But there is a happy ending to the story. Since losing her phone, Dena has seen her grades rise.