I would second goliedads post.
My only thought would be this. During all the interviews my son had during this process he never asked about campus based scholarships. He did however ask at the end of each discussion "If I am not offered a national scholarship what would my other options be to achieve the same goal" Most of those he spoke with explained about the SMP program, joining ROTC and competing for a 3 year scholarship, and a few mentioned that they may have campus scholarships and that he would be considered. A couple of the PMS's told him they were glad to see he was considering all his options and that they would contact him if he was not selected by the 2nd board to explain in greater detail any of the other options available. Luckily for him he was selected on the first round and he didn't need the other options.
I guess my point is that while asking directly about campus scholarships may not be a good idea, asking about what the other options are doesn't hurt. It gives the PMS the option to bring up the subject without the perspective cadet going fishing.
Now, once they are in ROTC tell them not to be afraid to ask for anything, over the past 3 years my son has received some wonderful oppertunities and great leadership positions by basically just walking in and asking for it, sometimes he's amazed that no one else asked.