The strong effect that background knowledge has on reading comprehension is one of the most stable findings in all of cognitive psychology (Paris & Stahl, 2005). Even early reading researchers from Gates (1931), Huey (1908), and Gray (1939) noted the relationship between background knowledge and reading.

Background knowledge, knowledge a reader, network or environment brings to any text or learning situation (Alexander, 1992; Anderson & Pearson, 1984) explains the greatest amount of variance in measures of comprehension, after accounting for the ability to decode text.

If you know about a topic you understand more complicated texts about a topic. ( Means & Voss, 1985). In fact reading researcher suggest at least three distinct areas of background knowledge as they construct meaning from informational text (Anderson & Pearson,1984):

• general world knowledge
• prior subject-matter knowledge,
• prior knowledge of text structure

• Organize background knowledge of topic and text structure with what they read (Graesser et al, 1994);
• Make intertextaul Links (Hartman, 1999; Kintsch & van Dijk, 1978);
• Use text structure to skim and scan (Englert & Hiebert, 1984);
• Use background knowledge to monitor comprehension (Duke & Pearson, 2002)
• Use background knowledge to question texts. (Paris, Wasik, & Turner, 1991; Duke & Pearson, 2002)
• Use background knowledge to for fx-up strateggies (Paris, Wasik, & Turner, 1991; Duke & Pearson, 2002)

• Use KWL charts to have students monitor how background knowledge changes and grows.
• Provide concept maps as pre and post measures of knowledge growth
• Use vocabulary quizzes and questions as proxies for growth in the classroom