You are confusing cause and effect:
Better Students Join Band.
Joining Band doesn't cause Better Students. If this was true, we'd by the entire 9th grade a fucking kazoo every year and add it to the curriculum.
"stare at the wall all day long?" What PLANET do you come from? Are you suggesting that human's are so unimaginative that without Marching Bands, the entire Entertainment Industy may be imperiled?
You don't get Cable TV do you?
What are students going to do with they have no outlet? If you want the answer go to an inner city school with no programs like band or football.
In high school they also do quite a bit of fundraising for those activities, and at football games they charge an admissions fee. At my school if you were student you could buy a pass for the year, and if you are parent you can buy a booster card for cheaper admission. Shit, I haven't been in high school for ten years and my dad still buys a GSL booster card so he can go to football games, and my neices basketball games.
I can't even say how many car washes I worked in high school to raise money for the sport I was playing. We also paid for our prom, and started raising money for it our freshmen year.
But I guess your answer to it all, is just make our kids watch Cable tv.