Young children are uniquely 
suited to learning a second language. The developing brain is hard-wired to acquire language. Never again will it be this natural or easy to acquire a language.
Research shows that children possess their greatest ability to absorb and retain languages before they reach adolescence. Young children across the world effortlessly pick up whatever language or languages they are exposed to. Researchers say that when you are young, you acquire language, rather than having to learn it. If you wait until you are older to start, language becomes something you must learn by rote and memorization. It then becomes work, and few people who start late with a second language ever succeed in becoming fluent with good accents. Children are less self-conscious than adults and not as afraid of getting things wrong or saying them incorrectly.
What researchers are saying:
“The power to learn language is so great in the young child that it doesn’t seem to matter how many languages you throw their way. They can learn as many as you allow them to hear systematically and regularly at the same time.”
Susan Curtis, linguistics professor at the University of California, Los Angeles.
“People who are bilingual have an advantage over the rest of us, and not just in terms of communication skills. The bilingual brain develops more densely, giving it an advantage in various abilities and skills, according to new research…brain imaging showed that bilingual speakers had denser gray matter compared with monolingual participants.”
Miranda Hitti -WebMD Medical News (Oct. 13, 2004)
Here is a link to an article from the American Council on the Teaching of Foreign Language (ACTFL) on the cognitive benefits of learning language:
http://www.actfl.org/i4a/pages/index.cfm?pageid=4724
