Just a suggestion.  If you are going to approach schools it is better to work from the bottom - up. Approach the kids first ( best if it's someone you know) to see their response. Grab the enthusiastic, ( at least two kids. Gives more credibilty and reinforcement when they are talking to the person in charge) walk them through the program until they are comfortable. Provide them with the tools; business card, flyers...
Have them approach the band, cheerleaders, et;. These activity direcors need to see it is something that as a whole everybody can do with the no trepidation and feel good about presenting it.

Real important is to let them know that this will tie in well with their other programs. You do not want to down play what they are already doing. The idea is to make them feel what they have done is important; yet what they can look forward to in the future is fun-draising in the 21st century. 

Maybe you could say to the activity directors ..Wouldn't it be nice if the congress gave us some of the money they waste on pork barreling and they had to  "throw bake sales".