"Backpack Kid" goes to prom! Just look at 16-year-old Russell Horning and his date for the night busting out into his signature "flossing" move he popularized on "SNL" during a performance alongside Katy Perry. Horning went to the New Haven, Conn., dance to surprise Libby Gardner, who had emailed him an invitation but never heard back! Little did Libby know, Amazon Teen was secretly planning the whole thing. InsideEdition.com's Leigh Scheps (http://twitter.com/LeighTVReporter) has more.