Senior Year 1st Semester: Failed a Class

So I’m currently a high school senior and I’ve already applied to all my colleges. 1st semester just finished and it turns out I got a 68, or a D+ in physics and I can’t do anything to change this.
I already finished 3 years of science so this was basically considered as an elective and not a required course for me.
I failed because the content was very tough and I was also juggling 5 AP courses (I got A’s in 2 of them).

I want to know how bad this D+ can affect my admission to colleges such as the University of California schools and the California State University schools.
My main concern is if they’ll revoke my admissions decision if I got in.

Revoke is not an issue for UC; they will know before they decide. The UCs require you to notify them of any grade below a C. And to confirm with any UC that accepts you that they received your notice. Details at http://admission.universityofcalifornia.edu/how-to-apply/after-you-apply/

Should you decide not to do this on hopes that maybe they won’t notice, they do notice. And it will go worse for you since you didn’t follow the requirements.

I fear you’re missing the real lesson here. Something is going wrong with how you study. Whether its how much time you spend studying or how you study, it behooves you to figure out what needs to change. In college, certainly at UCs, this is not an excessive workload nor will the classes get easier. And across the state, probably right there in your own HS, kids are taking a similar load and doing well.

your HS has dealt with this in the past. Speak to a GC as soon as possible.