+JMJ+
Learning the piano (or any instrument) will allow one to play the great Mass settings from Catholic composers. Likewise, a person can (and should) compose devotional "folk" music in honor of Our Lord, Our Lady and the saints.
Piano will, as was mentioned, help with IQ, motor skills and other cognitive and physical abilities.
Any sort of good, honest discipline can, of course, be offered to Our Lord for His glory and as a way to take "every though captive" and bring yet another area of one's life under the obedience of Christ.
Mary, Help of Christians, pray for us.
St. Cecilia, lover of music and of Our Lord, pray for us.
Sacred Heart of Jesus, have mercy on us.