AND UNLIKE JOB TRAINING, IT'S A SKILL THEY CAN USE:

Music is no cure-all, nor is it likely to turn your child into a Nobel Prize winner. But there is compelling evidence that it can boost children's academic performance and help fix some of our schools' most intractable problems.

*Music raises your IQ.

E. Glenn Schellenberg, a University of Toronto psychology professor, was skeptical about claims that music makes you smarter when he devised a 2004 study to assess its impact on IQ scores. He randomly assigned 132 first-graders to keyboard, singing or drama lessons, or no lessons at all. He figured that at the end of the school year, both music and drama students would show bumps in IQ scores, just because of "that experience of getting them out of the house." But something unexpected happened. The IQ scores of the music students increased more than those of the other groups.

Another Canadian study, this one of 48 preschoolers and published in 2011, found that verbal IQ increased after only 20 days of music training. In fact, the increase was five times that of a control group of preschoolers, who were given visual art lessons, says lead researcher Sylvain Moreno, an assistant professor of psychology at the University of Toronto. He found that music training enhanced the children's "executive function"--that is, their brains' ability to plan, organize, strategize and solve problems. And he found the effect in 90% of the children, an unusually high rate.

*Music training can reduce the academic gap between rich and poor districts.

The Harmony Project in Los Angeles gives free instrument lessons to children in impoverished neighborhoods. Margaret Martin, who founded the program in 2001, noticed that the program's students not only did better in school but also were more likely to graduate and to attend college.

To understand why, Northwestern University neurobiologist Nina Kraus spent two years tracking 44 6-to-9-year-olds in the program and then measured their brain activity. She found a significant increase in the music students' ability to process sounds, which is key to language, reading and focus in the classroom. Academic results bore that out: While the music students' reading scores held steady, scores for a control group that didn't receive lessons declined.

Prof. Kraus found similar results in a 2013 study published in Frontiers in Educational Psychology of 43 high-school students from impoverished neighborhoods in Chicago. Students randomly assigned to band or choir lessons showed significant increases in their ability to process sounds, while those in a control group, who were enrolled in a junior ROTC program, didn't. "A musician has to make sense of a complicated soundscape," Prof. Kraus says, which translates into an ability to understand language and to focus, for example, on what a teacher is saying in a noisy classroom.

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