Students can replace required courses for equivalent courses taken elsewhere. However, the university Residency Requirement requires students to complete at least 30 units at SJSU, of which 24 must be upper division, 12 must be in the major, and 9 must be general education.
To replace a required course by an equivalent course requires permission from the BSCS advisor. If the course is a Math, Computer Science, Computer Engineering, or Physics course, see an advisor in the corresponding department. Bring a syllabus from the course you took. Bring a catalog showing the prerequisites for the course. A copy of the text book would be useful, too. Also bring proof of the grade you received in this course.
Note that lower division courses can't be substituted for upper division courses, however in certain cases—Math 129A, for example—the requirement can be waived in lieu of some other course to be determined by your advisor.
As a last resort, students can challenge courses. This involves registering for the course, then taking the final exam in the first week or two. Note that not all professors will agree to do this as it involves a lot of work.
Virtually all of the lower division GE courses can be completed by equivalent courses at community colleges. Speak to GE advisors at the community college or at SJSU to get more information on this. It's a complicated subject and an SJSU GE advisor will ultimately evaluate the GE courses you have taken elsewhere and determine which SJSU GE requirements you have met.
Course equivalencies for the courses listed below are established and don't require approval from an advisor.