Considering that for the vast majority of history, marriage was done for financial and power purposes, I have no moral qualms with what the OP is doing. (I am not ashamed to say that finances were the primary factor pushing my spouse and I to get married, even if we did love each other. “Love” is such a new marriage “requirement” though…)
On a practical side, it’s just pretty dumb though as there’s no guarantee it would work and divorces can be messy depending on state laws.
Not worth IMO.
While I do think this is a terrible idea (because of the possibility of not working and the costs of lawyers to make sure you aren’t (in)advertently screwed over in the process), I think the people saying this is felony marriage fraud are wrong. I believe the only motivator for marriage that is illegal is to gain US citizenship. (http://www.justice.gov/usam/criminal-resource-manual-1948-marriage-fraud-8-usc-1325c-and-18-usc-1546) This would therefore not qualify as marriage fraud.
@StarsAndBoxes, if you’re genuinely thinking of doing this, go to a lawyer and find out the implications first. You should also talk to the financial aid office and tell them you’re thinking of marrying an OOS student and ask about it. When you say you’re going to marry someone, no one should be asking you if you love them – it’s more than implied, and it’s something only you two can decide. If you do get married, make sure you see a lawyer for a simple prenup first. It’s not just a piece of paper, it’s something that can simplify things if you decide to dissolve the marriage later.
On an “it’s none of my business” note, I’m a straight person who has always supported gay marriage, and thinks it was long overdue. However, there are people who would use this sort of thing as ammunition for lack of morals, etc, and you should be prepared for that. They won’t see that your goal is to help this woman get an education, and most won’t agree with your methods.