Kellie Pickler by Denise Truscello/WireImage.com Kellie Pickler by Denise Truscello/WireImage.com

Fox has announced the lineup for a celebrity edition of Are You Smarter Than a 5th Grader?, airing Sept. 6 as the hit quizzer's sophomore-season premiere, and benefiting charities. The A- and B-list names going for A+ scores are morning talk king Regis Philbin, American Idol alums Clay Aiken and Kellie Pickler, Extra's Billy Bush, skateboarder Tony Hawk and Miss America Lauren Nelson.