Here is a great list of resources to use at home.

You can learn more about the instruments of the orchestra and band on this interactive website, sponsored by the Nashville Symphony.

http://www.nashvillesymphony.org/nsokids

The Canadian National Arts Centre offers a comprehensive site that includes a short biography of Tchaikovsky and video of the National Arts Centre Orchestra playing an excerpt from his Symphony No. 4 in F Minor, Op. 36.

http://artsalive.ca/en/mus/index.asp

The Dallas Symphony Orchestra helps students identify the instruments of the orchestra through solo audio clips and performances with the orchestra.

http://www.dsokids.com

The Kennedy Center ArtsEdge program offers two interactive modules for budding orchestral experts. Perfect Pitch moves the orchestra to a baseball field, where students can see and hear the development of the orchestra from the Baroque period through today. Xploring Xtremes focuses on dynamics and tempo.

http://artsedge.kennedy-center.org/perfectpitch

www.artsedge.kennedy-center.org/exploring/xtremes

For more detailed descriptions of the elements of classical music, try Essentials of Music from W. W. Norton. 

http://www.essentialsofmusic.com