I know that the classes you take senior year matter, but how much do your grades in those classes matter? Do they matter as much as your previous years?
Your first semester Senior year is one-seventh of your transcript, supposedly the apex of your academic achievement — a year when competitive applicants are taking their MOST rigorous courses. Colleges see your senior class choices and achievement – which are some of the BEST indicators of future college success. What do you think?
IMHO, your three MOST important semesters are this one and your two Junior year semesters.
The first semester matters because some colleges will see A) What rigor of classes you are taking B) How you are dong in them. If you are taking 4 APs but getting C’s in them, a college may not think you are ready for college courses. The second semester it is important to keep your grades up and not slack off so all of a sudden there is a C or D.
I also have to say that if you are not doing well in a class, now is a good time to figure out how to improve. When you go to college and are struggling with a class, it will be better to have learned the skills in HS. So if you are not doing well, make sure you are:
Going to class
Doing the homework
Talk to the teacher
Get a tutor
Do extra problems
Form a study group