Good question! I would love to. I started this when I had very little money as a college student. I could have donated 100% of my money and not made a dent in an American education. With Tanzania I was able to fund a student with so little money, so the leverage was huge.
Eventually I would love to do more work in the US. I'm a postdoc now so I'm still not in a personal position to make a meaningful contribution to an American education, but one day I plan to get there.
Because I believe in putting your own nation first before others. It does matter whether you are helping your own people or other people. I will always chose for an American to get a better education over someone from another country if I had a choice.
It is not for him to pride himself who loveth his own country, but rather for him who loveth the whole world. The earth is but one country, and mankind its citizens.