How can a 14 year old get a work permit?

Next year i'm going to the rainforest in Peru to help people in need and to learn about it. I am required to earn a third of it, which is about 1,200 dollars. I have been working nonstop all summer and I've only made about 300. I am pretty sure Indiana allows you to be at least 14. I am 14. I know times are tough, but i will be determined to find a job. I do not think a lemonade stand will do me any good for a thousand dollars. :) i get good grades. how do i get a workers permit and how do I start?