I would suggest three ways:
First, he’ll need to look at some lower cost options, like in-state schools and community colleges. He might not like that idea, especially if his friends are going out of state, but that’s the best way to keep it affordable. After two years of working, going to school, and applying for scholarship money, he should have the option to transfer if he wants to.
Second, he needs to be looking for scholarships and grants, like right now. Notice that I didn’t mention student loans. Debt isn’t an option! Students have thousands of scholarships and grants available. If you really want to make sure your son gets financial help going to school, filling out applications for grants and scholarships should be their part-time job.
Finally, speaking of jobs, your son is going to need to get a job. He can work full time during the summer and part time during school. Since he’s living with you, almost all of that money can go toward his tuition. He can mow yards, deliver pizzas, work a mall kiosk—whatever it takes.
Remember, debt is not part of this situation! No matter what you do, make sure your son can go to school debt free.
Graduating from college with tens of thousands of dollars in debt is not a good plan.