I think it would be classified as service--my first for-pay job was working as a pinboy in a bowling alley, setting up pins. (It was the last bowling alley in town to need pinboys, and only six of twenty lanes needed them; the others were automatic. I learned about the casual cruelty of adults there--the casual cruelty of kids I already knew about.)

Later were jobs in farming and retail and construction, but that was the first one.