I'm from a small town in northern Oklahoma named Shidler. Our high school has about 80 kids 9-12. I'm volunteer coaching this year for the fishing team another guy started.  We won the state championship last year. Had more kids come out. Any idea how to try to get sponsors to get some underprivileged kids some equipment? We finished middle of the pack the last couple years at Pic Wick for nationals without much knowledge of the lake. 

Just straight up ask. Some companies even have a "charitable donation" link on their site. If not, call/email customer service of a bunch of different fishing companies and see what they say. I'd talk to local businesses too, especially fishing shops.

we used to raise money for pee wee and midget league football. raffles and golf tournaments seemed to make the most money. raffles are obviously less involved. and like jbab said, you gotta knock on some doors. thanks for volunteering your time to those kids. i hope you do well.