What are some great ways to make good money if you don't have a job?

I'm 14 years old, and I don't have a job yet so that's not an option for me. The thing I want more than anything in the world is my very own horse, and I feel like my parents would be happier to look into it if I had money ready. I need to raise at least 500 dollars to start with for the horse itself! I know it's a big job, but I can do it if I work hard.