The United States government already gives a $2000 tax credit per child every year, if the parents were responsible they could put that money into a good savings account for their child's college and they would have about $50,000 to use toward their child's education after they graduate high school.
This credit only reduces your tax bill. Even if you owe nothing the total allowed refund for
the credit would not exceed $1400 from what I understand Over 17 years (the claimable
age) that is just $23,800 assuming you have no tax bill over the 17 year period.
Not a reliable source of savings.
If you owe nothing you get $2000 per child age 0-17 that's $34,000 and after that as long as you claim them as a dependent you get $500 a year. If you were to put that in a good account every year with compound interest it should be around $50,000, even if you didn't make any interest on it it would still be $35,000 and you can do it tax free because it for education. I know people with 3 or 4 kids that get about a $10,000 refund every year and for some reason 3 months later they can't even pay their rent, but they have a new iphone, no clue how they blow the money so fast but to them its easy come, easy go.