 Daddy, why is the sky blue? To match your pretty eyes. Nope. See, all colors have wavelengths that are diffused by oxygen and nitrogen. Since blue has the shortest wavelength, it's diffused up to ten times more. Who taught you that? Mommy. By sixth grade, too many girls lose interest in math and science, which they'll need for most future jobs. Keep her interest alive. For ideas, go to girlsgotech.org. It's her future. Do the math. A public service message brought to you by Girl Scouts of the USA and the Ad Council.