http://www.helium.com/knowledge/243114-teaching-tips-guide-to-using-primary-sources-effectively-in-schools.xml Helium.com > Education (Other) > Teaching tips: Guide to using primary sources effectively in schools en-us Copyright Helium.com Wed, 15 Jul 2009 19:51:21 GMT Wed, 15 Jul 2009 19:51:21 GMT