The fact that you're getting paid at all is cool man. If you're doing this for a high school, and you do a good job (especially a private one) they will refer you to anyone in need, and more jobs will come. Not only that, but its also something to shove in your portfolio. Furthermore, I live in Canada, and 500$ American translates into about 850-900$ in Canadian cash. If you won't do it, tell'em to give me a call!