Try kiva.org or an investment in a Grameen bank. Anything you can contribute to education and better health will help people do better for themselves in the long run.

Population growth has turned out to be less of a problem than we thought 30 or 40 years ago. AAMOF, world population is expected to peak before the end of this century and then to decline as the economic value of children goes down, their mortality rates drop (So you don't have to have 8 babies to have 2 children that reach 25.) and women gain more control over their own bodies.

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