Yes; it is totally possible. In the prep-school, you are under no obligation at all. You are free to apply to as many of the academies as you want to. That's your choice. The only "Given" at going to a particular prep-school is that if you don't "Screw the Pooch". (Sorry, my terminology for getting in trouble, failing classes, doing something stupid, etc....); that you are pretty much guaranteed an appointment to the Air Force Academy. But you are totally free to apply to another military academy. Best of luck. Mike.....