I'm not an expert, but I assume the first questions they would ask would be:
1. What airline do you want mileage on?
2. If you don't have a favorite airline, what airlines could you use?
3. Do you want to fly domestic or international?
4. Would your daughter's college accept Amex?
With that information some of the experts here can give you some good advice. (I use the Citibank card and get AA miles.) Good luck!
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Middle_Seat