Lewis, Richard Monster’s Proof, 288 p. Simon and Schuster, 2009. Language: PG (the G-man’s name several times, plus a handful of other swears). Darby, 10, is a mathematical genius and so is his father. Since their mom left, Darby’s older sister Livey, has been holding the house together. With the reappearance of an old Etch-a-Sketch, Darby is back on the trail to prove an obscure formula – one the will make his imaginary friend, Bob, become real. But Bob has several ulterior motives, and though he cannot tell a lie, that doesn’t mean he has to give complete answers, either. It will take the help of two angels for Livey and Darby to rescue the world from Bob. While the mathematics may be a bit bewildering for some, there is plenty of action to keep the reader guessing throughout the reading. This book will need some help to sell it, however. MS – OPTIONAL. Cindy, Library-Teacher.