High school can be a very short 4 years. It is important to keep your goals in mind from the very start. The first four links will provide you with a general timeline and "things to keep in mind" as you go through your high school years. The last two links are a list of websites that will point you to the undergraduate admissions/scholarship pages so that you can begin to compare tuition costs along with possible scholarship options.
Colleges and universities want to see a "whole" person, so be sure to not only focus on your grades but focus on how you can be involved at HMA and in your local community and church. Remember that they will most likely not meet you in person through an interview, so who you are must be able to be "seen" on paper. Document all of your activities, accomplishments, volunteer projects, church involvement, and other after-school activities. And when the time comes for college applications, be sure to list everything you have done so that a "picture" of who you are can be clearly visible on your applications.
Each year that you are in high school will have an incredibly profound effect on college admissions and scholarships. Don't let a single year drastically alter your future. Work hard, study hard, be diligent, and don't be afraid to ask for help.