Summer course?

First off, and I believe this was mentioned to you (or another student) on different thread, Calc BC contains THE SAME material as Calc AB (your Math Requirement), but has additional subjects covered. It makes absolutely no sense to take Calc AB and BC concurrently, so I wouldn’t advise you to do it. If your high school will not let you take Calc BC in place of Calc AB, drop Calc BC and take regular physics. Yes, I’m advising you to drop Calc BC because it will appear to colleges that you are taking virtually identical courses at the same time. See: http://apcentral.collegeboard.com/apc/public/courses/220300.html

The other option which you suggested is to drop AP Music theory and take regular physics instead. AP Music theory is another of those AP courses considered “AP Lite” by selective colleges. IMHO, selective colleges would prefer you have regular physics over AP Music Theory or taking Calc AB and BC concurrently. So, you have two options right there to play with on your schedule.