I wanted to point out a couple of useful sites on the internet that can be very helpful in demonstrating the importance of music education as an important part of all students' development.
A very useful site with lots of information, research and resources is SupportMusic.com. They can even help you build your case for keeping your school's music program by addressing talking points to 13 common issues including: Music is not perceived as a core academic subject or districtwide budget cuts.
Another useful site is the American Music Conference. They also have a sizable listing of music related research.
For instance, did you know that middle school and high school students who participated in instrumental music scored significantly higher than their non-band peers in standardized tests. University studies conducted in Georgia and Texas found significant correlations between the number of years of instrumental music instruction and academic achievement in math, science and language arts.
Another important finding: A ten-year study, tracking more than 25,000 students, shows that music-making improves test scores. Regardless of socioeconomic background, music-making students get higher marks in standardized tests than those who had no music involvement. The test scores studied were not only standardized tests, such as the SAT, but also in reading proficiency exams.
Visit both of these sites and see why schools need more not less music instruction.