As a freshman or sophomore in high school you might not be thinking about college and what classes to take to get into the best colleges. But you should. 

College classes are not easy. Professors do not teach to you personally, but to 200+ students at once. You definitely do not get the same attention in college that you got in high school. College professors are some of the nicest teachers I've ever had, but it is impossible to make the same connections with them as your high school teachers. 

My advice to you is to take AP, AICE, and IB classes. Take the “hard” classes in high school and pass the exams. The amount of classes that I have placed out of that my friends still need to take is too many to count. I am taking classes as a freshman in college that some juniors are taking. Take the APs!!

If you are able to dual-enroll, dual-enroll. It was the best decision I have ever made. My suggestion for you is to take the harder math classes like calculus and statistics in high school through dual-enrolling or AP so you never need to take it at a hard college. All my friends are struggling with calculus. I personally am taking calculus this summer at my local community college since it is so much easier. 

Take all the classes you possibly can through dual-enrolling. It saved my life at UF. My work-load is way easier than some of my friends and I am way ahead of most freshman.  Make dual-enrolling your best friend. Trust me on this one.