Babysitting. Started about 12 years old getting paid to babysit, and then when I was in HS, it was a steady job. I was pretty much the only babysitter for 2 streets at the time. I also went to stay with my aunt in Ohio for the whole summer of my 16th birthday. I was like an Au pair for my cousin, who was 5.
Before I started babysitting, my mom used to pay me to iron. I probably started doing that when I was about 9 years old or so. I would get money for ironing handkerchiefs, certain tea towels, and pillow cases.