Dear useless girlfriend,
Like most women in this world, you would like to have your cake and eat it too. Not that I do not empathize with your insatiable demands for personal benefits, but I hope to appeal to the sense of logic which is underdeveloped in most women (or they just ignore it when convenient).
The situation appears that you are a busy person between school, basketball, and fornicating your equally useless boyfriend. Apparently you have no job and would like to add snowboarding to your allegedly rigorous schedule. You would like to find a non-commital employment which can achieve $25 a week or about $100 a month. Unfortunately, like money, time is a scare resource. You need to prioritze. Basketball, school, snowboard, boyfriend's cock; which cums first in your sense of priorities?
$25 a week really is not that much money, most girls spend that a week on their cell phones. There's an expense you can cut right there. How badly do you want to snowboard? To earn that in a job should only take you 2-6 hours. I am assuming you are relatively unskilled labour in a low minimum wage locale, else you would not be in this quandary, so you are probably near the upper end of the range.
Judging by your myspace pic, which I perved briefly, I would say you are attractive enough to prostitute your time at some restaurant and make decent tips if you wear the right clothing. I recommend this option, it puts something semi-meaningful on your resume, it's legal, more stable cash flows than babysitting, reasonable returns, and hopefully brings a creepy but affluent customer who can supplant your incumbent boyfriend and conveniently provide you the financing needed to snowboard. He might even be a nice guy considerate of your needs as a confused teenage female and may not be fixated on hooching your pre-adolescent cooch.
In conclusion, hook yourself out at a restaurant to get a start, then upgrade to a richer pimp/boyfriend.
I apologize for any insults, but it is a pleasure to burn naive newbs, I suggest you try it sometime.