Ideally, you would want scholarships that don't have restrictions such as tuition only because as a general rule - there is no tuition at USNA. However, there is a summer program (optional) called the National Outdoor Leadership School where Mids can spend time learning surviving skills in the great outdoors. If you want to do this program, you have to pay your own way. (USAFA calls this SERE and it is a mandatory part of the USAFA experience).
You can use 529 funds, personal funds, or scholarship funds (if you write a paper on the experience you can get a couple of college credits)
I don't know how many Mids actually go, but it is at least one example of where scholarship $s can be applied as 'tuition' at USNA.