What increases IQ? Apparently School and Music.

Schooling in general raises IQ by several points a year, based on research by Stephen Ceci, a professor of developmental psychology at Cornell, and others. "If you look at an IQ test, it asks things like, 'Who wrote Hamlet?' or 'Why do we pay for postage?' You are most likely to come across the answers in school," Dr. Ceci says. Even nonverbal abilities such as solving puzzles and spatial tasks may blossom because math classes today include visual reasoning with matrices, mazes, blocks or designs, he adds.

Music lessons are linked to higher IQ throughout life, according to research by E. Glenn Schellenberg, a psychology professor at the University of Toronto at Mississauga. Six years' lessons lifted children's IQ scores an average 7.5 points; those gains eroded to two points by college age, says a study published in 2006 in the Journal of Educational Psychology.

In a study this year, researchers at the University of Kansas found practicing musicians who are active for a decade or more continue to post higher IQs beyond age 60.

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