This article is about language acquisition from preschool through elementary school. By the age of 3, most children have acquired an almost adult-like understanding of syntactical constructions (Bates & Goodman, 1997). By the time they have entered first grade they have acquired their native language’s phonological system, and can produce almost all of the sounds of their native language (Graves, 1987). The mastery of vocabulary acquisition, though, is still vastly incomplete. In school, children develop additional word-learning strategies. Direct vocabulary instruction appears to contribute to vocabulary acquisition (Graves, 1987). Biemiller (2001) suggests that at least 80% of the words children acquire by the sixth grade are learned through direct instruction; children acquire root word meanings through direct explanations from parents, educators, and peers, and within texts. Although research on the best technique of direct vocabulary instruction is mixed, several conclusions concerning its overall efficacy can be made:
First, all instructional methods produce better word learning than no instruction. Second, no one method has been shown to be consistently superior. Third, there is advantage from methods that use a variety of techniques. Fourth, there is advantage from repeated exposures to the words to be learned. The simple version of these findings is that people tend to learn what they are taught, and more attention to what is being taught is useful. (Beck & McKeown, 1991, p. 805)
Direct instruction of words, then, needs to go beyond simply asking children to memorize a definition to providing children with repeated exposures to words, their definitions, and contextual information, and allowing the child to explore the meaning of the new words rather than simply memorizing them (Osborn & Armbruster, 2001). Three seemingly successful methods of direct vocabulary instruction include the keyword method (e.g., McDaniel & Pressley, 1984; Pressley, Levin, & Miller, 1982), semantic mapping (e.g., Johnson, Pittelman, & Heimlich, 1986), and semantic feature analysis (Anders & Bos, 1986). The keyword method encourages children to find a familiar word within the unfamiliar word (e.g., car from the novel word carlin, meaning old woman), and then connect the meaning of the novel word with an image associated with the familiar word (e.g., an old woman driving a car; Pressley et al., 1982).
McDaniel and Pressley (1984) found significantly greater definition recall with the keyword method in comparison to a context method for acquiring word meaning. Semantic mapping and semantic feature analysis involve graphically relating novel words to a familiar thematic concept, thereby activating students’ familiar experiences and concepts (Anders & Bos, 1986; Johnson et al., 1986).
In contrast with Biemiller’s assertion, others suggest that incidental learning provides the primary means of vocabulary acquisition from preschool through elementary school and beyond (e.g., Leung, 1992; Vocabulary Acquisition: A Primer 7 Nagy, Herman, & Anderson, 1985; Osborn & Armbruster, 2001). Comparing estimates of the number of words that children acquire through their school years with estimates of the number of words they acquire through direct instruction suggests an important role for incidental
learning. Leung (1992) explored vocabulary acquisition in oral contexts, using a repeated read-aloud with children in kindergarten and first grade. She found that read-alouds influenced children’s acquisition of words for familiar concepts, but did not significantly influence the acquisition of words representing unfamiliar concepts. Penno, Wilkinson and Moore (2002) assessed incidental word acquisition in children ages 5 years, 2 months to 8 years, 1 month using repeated read-alouds as the vehicle for providing an opportunity for incidental learning. Evidence of vocabulary acquisition from incidental learning was found. Adding some direct explanation of word meanings in the context of the read-alouds enhanced vocabulary acquisition. Brabham and Lynch-Brown (2002) also assessed word acquisition in repeated read-alouds, finding that first and third graders made vocabulary gains, but differentially depending on read-aloud style: students who were engaged in an interactive reading style in which word meanings were explained, or in a performance reading style where children were encouraged to ask questions before and after the story, displayed more vocabulary gains than children who simply experienced a read-aloud.
Werner and Kaplan (1950) assessed the acquisition of word meaning in oral contexts in elementary-school children (ages 8 years, 5 months–13 years, 5 months), finding that although children could make inferences about novel word meaning from oral context, older children (beginning around age 10–11) were more able to derive decontextualized meanings. McKeown (1985) also explored contextual word learning in
high- and low-verbal-ability fifth graders; students were presented with read-aloud sentences that progressively constrained the possible meanings of an unknown word. She found that high-ability fifth graders were significantly better than low-ability fifth graders at choosing, evaluating, and comparing contextual constraints on novel word meaning.
When children learn to read, their ability to derive word meanings from context extends from oral to written contexts. Jenkins, Stein, and Wysocki (1984) explored fifth graders’ ability to acquire word meanings incidentally, and found that students could acquire knowledge about previously unknown words in context-rich paragraphs even without
explicit instruction. Nagy et al. (1985) found similar results for average and above-average eighth graders, for contextually derived word knowledge utilizing natural texts. Shore and Kempe (1999) explored student’s partial knowledge of contextual words, finding that meaning-restrictive contexts allow students to limit and then infer possible word meanings. Sternberg and Powell (1983) explored the benefits of instructing students in three strategies to better utilize context in acquiring word meaning: selective encoding, selective combination, and selective comparison (Sternberg, 1987). Selective encoding asks students to distinguish between relevant and irrelevant cues that will aid in defining the word.
Students next use selective combination to decide which cues should be combined to construct the word’s meaning. Then students employ selective comparison to relate prior knowledge to the information derived from the context, to better define the unknown word. Buikema and Graves (1993) successfully taught a small group of seventh- and eighthgrade students strategies for utilizing context in defining words, combining several cues from Sternberg and Powell (1983) with an additional strategy for assessing a word’s sensual aspects (e.g., its appearance, its smell).
Fukkink and de Glopper (1998) performed a meta-analysis on studies that directly attempted to improve students’ ability to derive word meanings through context. They found that direct instruction in using contextual cues is effective, with a mean instructional effect of .43 standard deviation units. It appears therefore that students learn about words in both oral and written contexts, and that direct instruction in utilizing context more effectively positively influences their vocabulary acquisition.

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