After his dad disappears, thirteen-year-old Stanley joins the army during World War I and is assigned to the War Dog School, where he is partnered with a messenger dog named Bones and the two of them are sent to France. Interest Level: 5-8 Reading Level: 6.0 ATOS Book Level: 6 AR Interest Level: MG AR Points: 9 AR Quiz: 159267EN Reading Counts Level: 5.6 Reading Counts Points: 14 Lexile Measure: 870.