> In the US, we finance college students with grants and subsidized loans. But rather than making college affordable, this aid has had just the opposite effect by driving tuition up across the board.

Increasing price (outside of aid) isn't actually the opposite of the effect aid is intended to have -- subsidies always increase the cost before subsidy; the intent is that they will decrease the cost after subsidy for those receiving the subsidy since, under most reasonable supply/demand conditions, the amount of increase will be less than the amount of the subsidy.

And this would probably work fine for grants taken alone, but we can't really isolate the impacts.

Loans, however, aren't subsidies, they are cost-deferment measures. They aren't meant to make college more affordable (in terms of lower net cost after the policy) for those who get them, they are meant to allow people who could not afford college up-front but who would benefit economically from college so that college would be affordable if it could be paid for on a deferred basis can afford it.

College loans, however, are problematic because humans (in general, and those younger than mid-20s in particular) tend to be irrational and to -- as has, I believe, been shown in numerous studies -- overly discount deferred costs, so that loans have the effect of subsidies on near-term costs while at the same time just being deferred costs. So they increase the pre-policy cost without actually being a subsidy to those who qualify for them.