I wonder whether you might be able to get around the problem by helping out your target population while they’re still in high school.
In my community, a man who strongly supported music education in the public schools recently died. His family, with the support of others, is raising money in his memory to support efforts to help promising music students while they are still in high school – by helping them pay for instrument rentals, private lessons, summer music camps, and the like.
Might there be something similar you could do for the students you want to help? Something that would help them while they’re still in high school?