I already do chores around the house. And I babysit animals when their owners go away but I need more. People don't drive past my house so I can't have a lemonade stand and my mom won't drive me somewhere else so I can have it there. I am only Eleven so I can't babysit yet. How do I make extra money?
Go door to door in your neighborhood looking for work. (((NOTE: Only go to people you and your parents are familiar with – and TRUST))). Expain how you are looking to make some extra money for the summer and if they have anything that needs to be done.
If your a smart 11 years old, can follow instructions and complete tasks and chores as directed, you should have no problems finding some extra work. Just don't do anything your not capable of, or not experienced in (cutting wood w/ axe or chainsaw, dropping trees, cleaning out gutters, trapping animals).
Look for small yard chores (cleaning out flower beds, raking, spreading mulch, raking grass, washing cars, washing down driveways, sweeping stoops, small painting jobs (fences), walking pets, pet sitting or weeding). Just make sure a parent know what your doing, who your working for and give them times as to where you'll be. I have to do all these little chores myself because my kids aren't quit old enough to do them and there are no reliable kids in the area. Do a good job for one and you may get a reference for another job.
I made a fortune as kid finding and selling golf balls at a golf course by my house. These days, it would not be a good idea to be wandering the woods by yourself.