do errands for the neighbors, like walk their dogs, wash their cars, rake leaves, or get their groceries. Ask each neighbor to refer you to another that could use your help (called marketing yourself). Also, sell what you have but no longer need or want on eBay.
Tell friends and relatives you want cash for birthdays and holidays.
work
you can open up in your parents name
begging and borrowing
I know that allot of the trouble with people moving out is that they don't save their money so that they can pay all the expenses. I want to start saving early, but what kind of jobs can a 13 year old get?