NCSS's Middle Level Learning supplement from May/June 2009 had great web resources on Civil War Drummer Boys. 

• Camp Life, Gettysburg National Military Park 

• Child Soldiers in the Civil War, Digital History

• Civil War: Drummer Boys, eMINTS National Center

• The Union Army Uniform

• The Civil War Through a Child's Eye, American Memory, Library of Congress

• Johnny Clem, Ohio History Central

• Teaching with Documents: Civil War and Reconstruction, National Archives and Records Administration