Just a side comment from someone who works with undergrads daily.
Probably the greatest college-related financial gift a parent can give a child is to raise an adult who can stand on their own two feet when they're 18. Don't be their best buddy, and don't enable their teenage impulses. Teach them to navigate the world and have some grit. Babying a teenager is a parent consuming a child's future.
If a parent does the work of raising an adult, they can send them to the state flagship where full pop tuition is likely $15-20k, and they're never going to be seriously disadvantaged by that degree (bonus points if you happen to live in Michigan, California, etcetera). It's a sink-or-swim environment, but a kid who's ready for it can thrive and graduate in four years.
The alternative is to not do the work to raise an adult, and that puts a bunch of the burden for becoming a self-sufficient adult on the kid after they leave the house. Some flame out in state school. Some take seven years to graduate. Some go to a place with all manner of supports where the sticker price tuition is $50k+/year. All of these are extremely expensive options necessitated by people not raising their kids to function as adults. It translates a bunch of non-monetary costs for the parents during high school (conflict, angst, doubt, familial discord) into monetary costs for the child (student loans). Parents are essentially having colleges raise their kids to adulthood (i.e. parenting) at the child's expense (rather than their own), often crippling that child's financial life for the foreseeable future.
The point here is that "paying" for a child's education can be financial, but it can also be in the form of doing all the unpleasant stuff to get a kid ready for the world. Raising an independent kid who can hack it in a sink-or-swim environment can easily be worth 100k+ to that child.