With the kids getting older and my iTunes/MP3 collection growing I introduced the kids to burning CDs. I brought each one down to my work Mac and had them select enough of their favorite songs to fill a CD. They have been a smash hit. Each of the kids bedrooms has their own radio (with CD player) that they can listen to whenever, but usually at bedtime. I've been hearing the CDs at bedtime, on the main stereo, and even on my eldest's walkman.
And there's the problem. My little system in the office downstairs can belt out the tunes, but it can't compete with three kids and the home audio system upstairs. May be time to invest in a headset.