In fact, research has shown that if kids are not exposed to music (particularly fixed pitch instruments such as the piano) by age 10, those neural pathways close forever.

One example is perfect pitch hearing. It is both a genetic gift and something that needs to be developed. If your child has the propensity for perfect pitch hearing but was never exposed to a fixed pitch instrument (say piano lessons) by age 10, the child will never have or be able to develop perfect pitch hearing though relative pitch hearing can be developed at any age (knowing the note relative to another).

Why would perfect pitch hearing be useful? Relative pitch instruments such a violin, flute etc. rely on the musician finding the pitch but my sister, who has perfect pitch hearing, is able to take any jingle or song that she hears and immediately — with the greatest of ease — bang it out on the piano.

Music is a precious gift to kids that starts with a joyful activity to do adults whether at home or in a class. I really like your ideas to introduce music to kids at a young age.