Go back to banks giving loans for education, not the government. When a student goes in to get a loan they need to go through a cost/benefit analysis with the bank to ensure that the degree they seek is worth the tuition. If not, the bank says no and they need to seek funding, or think about their choices more.
The current system, in which taxpayers are on the hook, means people can rack up debt for degrees that will never earn them enough to pay off. This will also force colleges and Universities to cut fat and reduce tuition to become more competitive. While also teaching only those subjects that matter and not pet projects to indoctrinate our society.