Chances for UC's?

I’m currently a high school Junior in Southern California. I have a 2350 on my SAT, 800 on Math II, and an 800 in physics. I have taken 8 AP tests during my sophomore and freshman year, (Physics C Mech, Physics C E&M, Physics B, AP Calc BC, AP Calc AB, AP Music Theory, AP World History, and AP Chinese) and received 5’s on all of them except for AP Music Theory, in which I received a 4. My GPA is a 4.15 including freshman year, and a 4.49 without it (I transferred schools after freshman year, and honors classes did not count as weighted, so my freshman year GPA significantly reduces my average) My current class schedule includes AP Chem( which I am struggling in, will probably get a B in this semester), Multivariable Calculus, Honors English III, Spanish II(I took AP Chinese freshman year, so I had to start a new language to fulfill my language requirement), AP Computer Science, and guitar. I have straight A’s (excluding freshman year), but I think I might get a B in AP Chem this semester, due to not doing so well on one of the two tests this semester.

Extracurriculars include being captain of the varsity tennis team at my school, (we are working to win CIF this year) an integral part of the build team and drive team of my school’s robotics club (we reached regional finals, despite this being the first year we have participated), playing the piano for 10 years and winning the state improvisation competition, and the operation of a 1,000 student pen-pal program with disadvantaged children in rural china, working with a non-profit in China. I plan to intern there in the summer. So my question is: from previous experience, what are my chances of obtaining admission to schools such as UC Berkeley, UCLA, UCSD, or even other prestigious schools such as some of the Ivies or Stanford?

You have a very good chance at the UC’s listed. Stanford is a Reach for everyone but you will be a competitive applicant. Make sure you spend time on your essays which will contribute to your overall application. Good Luck.