paperboy, mowing your neighbours lawns car washing etc.
Deliver newspapers,mow lawns,run errands,wash cars,walk dogs.
When I was around 11-12, I learned small engine repair by going through my grandfathers courses and working on them with him. I'd go to the "large item dropoff" at the local schools in the spring and get lawnmowers and rototillers, which people throw a LOT of away in the spring when they won't start. It always was merely a few dollars in tune up parts, or even just bad gas or empty, and I'd clean and fix them up and sell them for 50-100 dollars. I'd also mow lawns, do chore type stuff.
Later, I worked at a general store, and a golf course. Outside jobs are always good :-) . The "office" will crinkle your soul all up and then soak it in salt water and dog doo...
help older folks in your neighborhood any way you can; mowing, carrying in groceries, washing windows
think of doing jobs most people hate to do and you'll be busy -- clean out a garage, pull weeds, rake leaves, trim around fences, etc.
Pup-walking, babysitting, chores.