Quite possibly. +1 to raimius... I validated 4 courses, should have tried to validate a 5th, and am SO glad looking down the road that I have that space in my schedule.
You will take the validation exams for Math and Chemistry while you are here; college courses may factor in, but it's mostly your performance on those tests. English is at USAFA's discretion... whenever you get Appointee instructions, you should be able to find out whether your course counts for validation. I personally took AP and validated freshman English, which was a good choice.