• Most students need instruction in the technical vocabulary of a subject area to learn the concepts and meanings of terms. (Thelen, 1986; Vacca & Vacca, 2001) 
  • 70 percent of the most frequently used common words have multiple meanings. Students need a mindset that alerts them to this. (Lederer, 1991)
  • Vocabulary knowledge is a principal contributor to comprehension. Some experts believe it accounts for 70 to 80 percent. (Anderson & Freebody, 1981; Davis, 1972; Pearson, 1984; Thelen, 1986)
  • Words are learned by bridging from known words/concepts to unknown words (linking prior knowledge with new knowledge). (Johnson & Pearson, 1984; Rupley, Logan & Nichols, 1999)