Also, know that the "I can see myself in purple and white / maroon and gold / [any color] and [any other color]" is a cliche of the "Why us" essay, but some students can't resist. Fine. If you're going to use it, though, at least get the team names and colors right. I've heard more than one admissions officer say that a screw-up like this can immediately disqualify an application. I'm not saying it definitely will, or that this is true for all admissions officers--some probably don't care--but don't give them a reason to put you in the "no" pile. Do your research. (And the USC colors are not red and yellow, incidentally, but "USC Cardinal" and "USC Gold.")
The GPA confusion doesn't stop here. Colleges also want to make sure that a student's GPA reflects grades in core academic courses, not a bunch of padding. Thus, a lot of colleges will calculate a GPA that is different from both a student's weighted or unweighted GPA. Many colleges will look just at English , Math , Social Studies , Foreign Language and Science grades. Grades in gym, wood working, cooking, music, health, theatre and other areas will not be given nearly as much consideration in the admissions process (this isn't to say that colleges don't want students to take classes in the arts—they do).