Colleges tended to look more at SAT scores and extracurricular activities, as well as what
kinds of classes I was taking when I started looking at colleges. On SAT scores alone, you can get pretty far. As far as kinds of classes: you can get a 4.0 average taking PE and the basics all through school, but if you do decently in AP classes or classes that are "advanced" or honors versions of regular classes, it looks good. And as far as college classes go, take an AP class and that's what one quarter/semester for one class is like in college. You'll undoubtedly have some kind of shock on your first week of college, so you might as well get used to doing more work with less time.
Personally, my GPA in high school was somewhere in the range of 3.0 to 3.4. I know I didn't graduate with any of the fancy honors or anything. But I did take some of the hardest classes the school offered (without doing Running Start), I was a varsity athlete, and I worked 28 hours a week (which is full-time, during school, for a person under 18 in washington state). I did well on my SATs, but I took them several times. Yeah, it was slightly expensive, but with that kind of test you don't want to pile all of your chances into one test-taking session. Depending on the college, they might take your best test or your best scores in each of math and verbal.
And don't forget to have fun! Highschool is when you have near zero consequences for things you do; minus the obvious stuff like crimes, drugs, becoming a dad, etc.
. Apparently it's the hardest year, especially since colleges are looking extremely close at you. Guess I need to bust my butt from the start huh? At least im not going through the anxiety that my younger sisters (twins) are going through, Freshmen year 
. Should be another wonderful experience i'm sure.
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