Summer School

So I got my final mark back for Grade 11 english and it was 96%. I am hoping to prepare for early admissions for university (Psychology BA). Would it be a smart idea to take my Grade 12 english in the summer or am I able to simply wait till next year to do it? Will my grades be enough to simply reflect on my abilities? (Keep in mind I also took a 4M course that I got 90% in).

(Not rage-bait, I actually need advice)