In a recent paper presented at the National Association of Scholars conference, Sandra Stotsky, Research Scholar in the School of Education at Northeastern University, expresses her dismay over the lack of K-12 teachers' knowledge of U.S. History. Stotsky draws upon her experience as a reviewer of applications for Traditional American History grants, as administrator in the Massachusetts Department of Education, and as director of a summer institute for history and government teachers, to demonstrate the utter ignorance and even disdain for fundamentally critical events and foundational principles in US history among many K-12 educators and the ed school faculty that trains them (most notably, the Constitution itself, which was accused by one dean of ed as something that should be viewed negatively because "it legalized slavery").
To see the paper in its entirety, contact Dr. Stotsky and she'll be happy to send you a copy.