I just read this really interesting article on how schools in Colorado are finding that in the quest to raise standards and achievement that data alone is a blunt tool; student voice sharpens this.
Their recommendations are excellent, especially:
Utilize student-led outreach to capture feedback from disengaged students.
Have a read: http://blog.ednewscolorado.org/2010/01/05/in-r2t-student-voice-will-sharpen-blunt-instruments/