The foundation of language development is established during the preschool and early elementary school years. School-age children, however, continue to refine their language skills in several domains. For example, their understanding of word meaning, or semantic development, continues throughout middle childhood. A first grader may know the meaning of 8,000 to 14,000 words, but a high-schooler knows 80,000 words (Owens, 1996). These numbers are equivalent to the acquisition of 6,200 words per year between first grade and graduating from high school. The understanding that words have multiple meanings also increases. This more complex understanding of word use may be attributed, in part, to cognitive development.

With the advancement of cognition children become better communicators and possess a more sophisticated sense of humor. A related advancement is that school-age children also begin to comprehend the use of idioms, such as “Who let the cat out of the bag?” Research shows that the comprehension of multiple word use, idioms, and forms of sarcasm may not occur until adolescence (Bloom, 1998). Semantic development in middle childhood seems to rely heavily on the context of the conversation and children’s ability to figure out the meaning of a word or phrase by what another person intended to say, rather than a literal interpretation of word choice (Baumann, Font, Edwards, & Boland, 2005; Cain, Oakhill, & Elbro, 2003).

Syntax development, or grammatical understanding and construction, expands during middle childhood. Children begin to understand the difference between active and passive voice (O’Grady, 1997). If given a toy car and truck and asked to show the experimenter “the car hit the truck” and “the car was hit by the truck,” a 10-year-old is more likely than a 6-year-old to play out the scene of both statements correctly. The older child will listen to the meaning of the statements rather than automatically link the action of the verb to the nearest noun. Older children also begin to understand and use more sophisticated syntactical rules, such as the correct use of subject-verb and noun-pronoun agreement, correct uses of that and which to introduce subordinate clauses, and the proper use of punctuation such as colons and semicolons. During middle childhood, children also begin to learn how to use the articles a and the correctly as well as understand connectives, such as but, although, yet, however, and unless (Vion & Colas, 2004).

Middle childhood is also the period in which children improve on the pragma-tics of language, or the social etiquette of language. For example, school-age children become better at maintaining and contributing to a conversation by asking questions and adding information. Between ages 5 and 9, children become better at shading, or changing the topic during a conversation. They do so more gradually and tactfully than younger children. This results from an increasing awareness of the needs of the listener. As children move through middle childhood they become more aware of when they are misunderstood and do a better job of clarifying their meaning by changing or adding words to their sentences (Ninio & Snow, 1996).

Compared to preschool and early elementary schoolchildren, children from 6 to 12 years of age are more effective communicators, use more complex grammatical constructions, and are more aware of their role as a listener and communicator within multiple contexts. Greater diversity among language skills in older children results largely from environmental factors. Children with larger vocabularies, more complex grammar, and social language manners have been shown to come from homes with two parents and parents with higher educational backgrounds and income levels. They also converse with their parents more often and have more positive speech interactions with them (Hoff & Tian, 2005; Weigel, Martin, & Bennett, 2005). The differences in language development influenced by these factors are evident by kindergarten and remain stable through adolescence (Farkas & Beron, 2004).

One’s cultural background has been shown to influence language development as well. In the development of pragmatics, for example, American children often argue with their older siblings and sometimes speak to them with disrespect. In contrast, children from Japan are expected to speak to elders, which includes older siblings, with respect at all times. In Western societies children are expected to speak up and ask questions when they have them. But Mexican American and Southeast Asian communities, as well as some African American communities from the Southeast, teach children to engage in conversation with an adult only when the adult initiates the conversation (Grant & Gomez, 2001). Thus, vocabulary, grammar use, and pragmatics are influenced by the language culture that surrounds the child. Children’s language development will affect their ability to learn in school and converse with others (Craig & Washington, 2004; Gonzalez, 2005).