What AP Credit Can I Get?
GMU has a list of courses and their AP exam equivalents, plus information about how to get credit.
In addition to various AP exams which can give you general education credit, the Computer Science A Exams can give you credit for CS112 if you pass with a 4 or 5.
There are similar rules for a variety of subjects which can help with the CS major requirements, notably Calculus (Math 113 and Math 114).
What IB Credit Can I Get?
A score on the IB Computer Science Exam of 4 qualifies the student for credit in CS112, and a score of 5 qualifies the student for credit in CS211.