Make some homemade wine and sell it:
This is illegal for a 15 year old kid and you should not do this... so its real simple you take sugar (dissolved in water) , kool aid packets any flavor (grape is the obvious) and yeast combine them in a bottle. place a balloon with pin pricks in it on top and wait two weeks. after the two weeks strain the wine... it is now potent and you can get drunk but like all fine wines it is better aged. place a cap on wine and let sit for 1-2 months.....Volla cheap ass house wine that you could easily sell for large amount of money to high school kids.
i have been doing this for a while about 25 cents of wine to fill a forty bottle and it gets you mad drunk and a even worse hangover.