Distance. How far are you willing to travel? Do you want to stay as close to home as possible, or are you willing to go far away? (If you go a really long way, consider that you may not get to see your family except at Christmas and maybe spring break.) Or do you want something in between?
Location. Do you like big cities, or do you prefer a rural environment? Or something in between, like a suburban setting? What about a drastic change in climate? If you've lived in Florida all your life and are considering a college in Minnesota, you're gonna need something warmer than a sweatshirt with your high school logo on it.
Size. Some Christian colleges have thousands of students. Some only have a few hundred. Would you like knowing most of your classmates, or would you rather blend into a larger campus? Where would you best fit in?
Admissions requirements. Colleges vary greatly in their standards for admission. Some schools are quite difficult to get into, others are much easier, and there are many in between the two extremes. If you're not sure whether you should consider a school because of its academic requirements, consult your guidance counselor.
Major. If you don't know what you want to study in college, don't worry. You're hardly alone. Half of all students end up changing their majors anyway. You usually don't have to decide on one until your sophomore year. So just pick a school that offers a wide variety of major programs.
Cost. Cost will eventually be a factor, but don't let it bog you down right now. When you're still very early in the decision-making process, it's not a huge concern. Yes, college can be expensive. But keep in mind that you'll rarely pay the full sticker price.
Financial aid from the government, private sources, and the colleges themselves is available to cut the costs. When it comes time to apply to your top colleges, you'll get financial aid packages that will give you a better feel for what you can—and can't—afford. Till then, don't sweat it too much.
Spiritual climate. If you're considering a Christian college, the spiritual life on campus will likely be strong. Still, ask about growth opportunities when you begin investigating schools. Ask about student fellowships, the campus chapel, nearby churches (you'll want to plug into a local church), and service and missions opportunities.
Also, most Christian schools have a statement of faith, which outlines their beliefs about God, Jesus Christ, the Holy Spirit, the Bible and other important issues of faith. Study this statement carefully, and ask yourself if you agree with it. It might be OK to disagree with minor details, but many items will be non-negotiable—things like the fact that Jesus was resurrected and other vital Christian doctrines.