Are you the only (or one of the few) freshman in that class? If so, you probably already took the course they offer at your high school for your grade level during your middle school years. This was the situation with the two freshmen who were in my sophomore-dominated AP Bio class. They had already taken Intercooridinated Science, which is the course ninth graders at my school are required to take, and so were given the opportunity to advance to biology, which comes next in their chronological order of science courses. I was also in the same situation as you for my Spanish 3 class during my freshman year. My middle school, being one of the very few, offered Spanish 1 and 2 and that is why I was placed in Spanish 3 during my freshman year while all my ninth grader friends were in Spanish 1 ( not because I was smarter than them, sorry to burst your bubble.)

If, however, there are many other freshmen as well in your class, it probably means that the juniors and seniors either failed the course previously or are taking it now because they did not take it before.

Last, there is a possibility that your high school is very disorganized and do not have set courses for each grade level. Let’s hope this is not the case.