Mrs. Hall's desk is overflowing with new pencils! But why are there so many? Be a math detective along with the kids at Lincoln Elementary and help solve this pick-your-own-path mystery. Use your math skills and knowledge of place value to solve the case. Choose the right answer, and advance to the next clue. Choose the wrong answer, and clear text and visuals explain the math and encourage you, the reader, to try again. Friendly illustrations with a diverse cast of relatable characters will engage readers, while clear math explanations support CCSS standards for second-grade math.