The scientific research on vocabulary instruction reveals that most vocabulary is acquired incidentally through indirect exposure to words. Students can acquire vocabulary incidentally by engaging in rich oral-language experiences at home and at school, listening to books read aloud to them, and reading widely on their own. Reading volume is very important in terms of long-term vocabulary development (Cunningham and Stanovich, 1998). Kamil and Hiebert (2005) reason that extensive reading gives students repeated or multiple exposures to words and is also one of the means by which students see vocabulary in rich contexts. Cunningham (2005) recommends providing structured read-aloud and discussion sessions and extending independent reading experiences outside school hours to encourage vocabulary growth in students.
Instruction for English language learners (ELLs)
An increasing number of students come from homes in which English is not the primary language. From 1979 to 2003, the number of students who spoke English with difficulty increased by 124 percent (National Center for Education Statistics, 2005). In 2003, students who spoke English with difficulty represented approximately 5 percent of the school population up from 3 percent in 1979.
Not surprisingly, vocabulary development is especially important for English-language learners (ELLs). Poor vocabulary is a serious issue for these students (Calderon et al., 2005). ELLs who have deficits in their vocabulary are less able to comprehend text at grade level than their English-only (EO) peers (August et al., 2005). Findings indicate that research-based strategies used with EO students are also effective with ELLs, although the strategies must be adapted to strengths and needs of ELLs (Calderon et al., 2005).
Diane August and her colleagues (2005) suggest several strategies that appear to be especially valuable for building the vocabularies of ELLs. These strategies include taking advantage of students' first language if the language shares cognates with English, teaching the meaning of basic words, and providing sufficient review and reinforcement. Because English and Spanish share a large number of cognate pairs, the first instructional strategy is especially useful for Spanish-speaking ELLs. These students can draw on their cognate knowledge as a means of figuring out unfamiliar words in English. A second instructional strategy for ELLs is learning the meanings of basic wordswords that most EO students already know. Basic words can be found on lists, such as the Dale-Chall List (Chall and Dale, 1995). A third instructional strategy that ELLs particularly benefit from is review and reinforcement. These methods include read-alouds, teacher-directed activities, listening to audiotapes, activities to extend word use outside of the classroom, and parent involvement.