Your work is pretty good. Some advice:
1. Be professional. Have a contract, pay tax, etc. Act like a professional.
2. Don't be "the cheap guy" or "the free guy". Charge what is appropriate for your skill level, not your age level. If you handle yourself in a professional manner and produce professional quality work, there is simply no reason why you shouldn't get paid accordingly. No reason! If it has value to someone they should pay for value received. Many will argue it also has value to you (portfolio). Indeed it does, so only you can decide how much you are willing to discount because of this. Having an opportunity to shoot a high profile person or event can represent value to you, so in those instances you may want to price accordingly, but don't sell your services short.
3. I would resist shooting for free in favor of pro bono work, and always assign a fair market value to this work before applying a discount or free status to it. This tells all, your work has value, and establishes a perceived value.
4. Shoot for the The Yearbook or school paper. They qualify as pro bono in my book. Both of these present perfect opportunities to pitch photo ideas. Suggest a photojournalistic feature that you can do for the paper. What can you do a photo story on? A day in the life of your Principal perhaps. Same goes for yearbook. How can a series of your shots tell a story? A great chance for you to call the shots.
5. Only show your best work. Be careful not to let emotion influence your choices. Don't feature a poor shot of a VIP just because you think someone would be impressed. The shot of Malachi doing nothing means nothing to me and others.