AME R I CAN PUB LI C SCHOO L L W EIGHTH EDITION Ke rn lexa nd er Professor University of I ll i nois Urbana-Champaign M Davi d l exander Professor Virginia Tech B l a cksburg ~ • • 5 W SWOR T H ~ , EN GA GE L ear ni ng A us tr al ia · B ra zi l · Japan· Kor e a · Me x i co S i ng ap or e· S pa in · Uni ted Kingdo m Unite d States