Over a quarter million underage British boys fought on the Allied front lines of the Great War, but not all of them fought on the battlefield-some fought beneath it, as revealed in this middle-grade historical adventure about a deadly underground mission.Secret Soldiers follows the journey of Thomas, a thirteen-year-old coal miner, who lies about his age to join the Claykickers, a specialized crew of soldiers known as "tunnelers, " in hopes of finding his missing older brother. Thomas works in the tunnels of the Western Front alongside three other soldier boys whose constant bickering and inexperience in mining may prove more lethal than the enemy digging toward them. But as they burrow deeper beneath the battlefield, the boys discover the men they hope to become and forge a bond of brotherhood. Secret Soldiers is another stunning story of strength, perseverance, and love from Keely Hutton.This title has common core connections.