Anyone looking for an easily accessible music appreciation course for kids should investigate The Classic Composers series from International Masters Publishers. It's a Time-Life send-you-one-disc-of-our-choosing-every-three-weeks kind of a deal. I got a sample disc (Mozart) in the mail yesterday. I usually just throw those things in the trash, but this had an actual CD in it, so I checked it out. It's pretty cool, actually. Each CD comes with a 24-page booklet detailing the composer's bio, a "turning point" in his life, "life and times," "In [historical Context," a listener's guide, the composer's influences and ends with a 20 question quiz (answers provided).
The CD itself comes with ~60 minutes of the composers "greatest hits." The Mozart CD includes the overture to the Marriage of Figaro, the Clarinet Concerto in B Flat Major, the Piano Concerto No. 21 "Elvira Madigan", "Eine Kleine Nachtmusik," the first movement of the "Sinfonia Concertante" (my favorite) and some others, recorded by well-known ensembles. Clearly none of this is in depth information--more of a taste--but from the sample and what I can tell from the promotional literature they sent, it's enough to introduce kids to classical music without overwhelming them.
Yes, they send a junky free gift with your order. "Buy as many as you want, cancel anytime." We decided to get a couple and see if they're all as useful as the Mozart cd is.