First of all, don't listen to anyone who tells you "penny stocks are crap," "don't throw away your money," etc. Penny stocks are very profitable, just you need to do these things:
1). Learn to read charts (and maybe Level 2 quotes, those are helpful) - first and most important step. Charts and indicators are the secrets to penny stock happiness. Get started here:
http://www.stockhideout.com/video-text-chart-lessons/
2) Get your feet wet - paper trade (fake trade) before you start using real money. Go here and start a new paper trading account
http://www.marketwatch.com/game/
3) Set up an account at a broker that is penny stock friendly (the best in my opinion are TD Ameritrade, Etrade and Zecco, although Zecco has some restrictions, it is the cheapest commission-wise)
4) Follow no one - one dangerous thing about penny stocks is that there are tons of pumpers out there, that is, people who promote penny stocks to make them out to be better than they are. It's fine and helpful if you have a stock chatroom that you can go to each day for running stocks, but don't listen to the pumpers. This is my favorite:
http://chat.stockhideout.com/flashcoms/index_ads.php
5) Make money!!
Other things:
You might want to have a real time Level 2 quote service, as well as a real-time chart service. Some options (although they are a little expensive):
http://www.equityfeed.com/
http://stockcharts.com/help/doku.php?id=support:services
and
never get into a stock that doesn't have volume (a lot of shareholders)!
BTW, I know its hard to believe but I'm only 14 right now, 15 on the 15th! Hope I helped ;)