for grandkids, i would suggest helping them pay off student loans after they get a "good" education. Since it's my money, i get to decide what "good" means. If their major includes the word "studies" in it, they're on their own. If their major implies a c*reer path within it (engineering, biology, chemistry, education, etc. Etc.) then i'm all in - if they graduate and get a j*b.
Once they go through the fafsa process and pick a "reasonable" school and see how much they have to borrow, hopefully they will base at least some of their decisions on what their education will actually cost (someone.) if they are unaware that grams and gramps might be willing to kick in at some point, they be a bit less free with someone else's money.
I've known too many families who more or less let their kids pick a school and a major that sounded "cool" and then were willing to pay for the kid's expenses. When the kids/parents/grand parents find out a major in theater studies qualifies the kid to apply for 5 positions out of 200 similar graduates - or to drive a cab, it's too late. I think kids should be on the hook for as much as possible and w*rk as much as possible so they will appreciate their education. Then old grams and gramps can step in and help save the day when the kids are getting started in the real world.
Just my opinion and i'm sure i'm a minority opinion on this subject. By the way, that's how we did it with our kids. It was rather successful if i say so myself. The kids are successful and had relatively little debt for us to help them pay. Ymmv