The Carnival of the Animals (Le carnaval des animaux) is an instrumental suite of fourteen movements by the French composer Camille Saint-Saëns. Most of the movements depict a different animal or set of animals with a variety of instruments. A very accessible instrumental piece for children, it lends itself to creative movement and discovery of different instruments and their sounds. (It is 25 minutes long.)
Here is the descriptions of all of the movements and more about the piece: The Carnival of the Animals I recommend after listening to The Carnival of the Animals on the above video, to get a CD of it out of the library. On the video are some ads (which is the downside of youtube) - but overall it is initially helpful for visually associating the animals with the movements. Listening to the CD, you can challenge your children to identify both the animal and instruments used - a great activity for car rides!