Is it possible for my class rank to go higher?

I just finished my freshman year of high school, and I graduated number 7 out of around 90 freshmen. I didn't do my best this year and my GPA was 4.5 weighted. If I got all A+'s sophmore year, would my class rank go up enough to make it to the top three? The top 3 students this year had straight A+'s, and if they continue to get the same grades next year, wouldn't I be unable to catch up to them because of my grades this year? Also, do colleges look at class rank or GPA? Or do they look at specific grades in each quarter? Is it okay if I got a few B's this year?