Have you visited Toni Thiesen's Wikispace?  She is a recent teacher of the
year and has an amazing wikispace with countless resources.  The question,
Why learn a foreign language? has a few links and documents.  Here is her
main wikispace site along with links to answer the question:

http://tonitheisen.wikispaces.com/home


http://www.actfl.org/i4a/pages/index.cfm?pageid=4524#Attitudes

http://lhsfrenchclasses.wikispaces.com/The+importance+of+learning+French+in+the+21st+century

http://lhsfrenchclasses.wikispaces.com/Learning+Foreign+Languages+at+an+Early+Age

The American Association of Teachers of French now has a Commission on Advocacy to defend your French program, whether you are a member or not. For more information, click here. (Much of this information may be of interest to teachers of other languages as well.)

Do you need research to defend or build your program? This document is a compilation of resources on the benefits of learning languages from the NEA website. Take a look! There's lots of valuable information. Thanks to Grace Leavitt for submitting it.

Gisela Hoecherl Alden has put together a marvelous brochure describing reasons for learning languages. It is suitable for students, parents, school board members--anyone thinking about language learning. Please feel free to download it and to distribute it as you see fit.