we would do a phased approach. But it hasn't been needed for my first two as they make bank at their PT jobs and support themselves fine. I would suggest not necessarily promising money to your kids until you know they need it. My third child might need some help (although he's making pretty good money at his job too). Because we haven't told him we'll help him, he's saving vigorously. But if needed, we'll help him with a phased approach. We can also move the 529 money from the older two who don't need it into his account (another reason not to promise it/spend it until you need to).