Since 2006 St. Jude Children's Research Hospital has been developing Cure4Kids for Kids, a school-based outreach program to educate children about cancer and healthy lifestyles with a focus on cancer prevention. An evaluation of student knowledge acquisition and retention for the program at the Grade-4 level was conducted during the 2010-2011 school year. Preliminary results of this evaluation are outlined with some of the challenges for long-term program evaluation of cancer prevention programs.