This book uses math and science to help students learn about mountains. Math challenge questions provide students with the opportunity to apply math skills as they learn about the characteristics of mountains. Real World Math: Geography. 21st Century Skills Library Interest Level: 3-6 Reading Level: 5.2 ATOS Book Level: 5.4 AR Interest Level: MG AR Points: .5 AR Quiz: 131856EN Lexile Measure: 390.