I'm a bit surprised by the sudden and apparently broad concern in the rigor of educational research cited by the President in his State of the Union speech, considering the extreme flimsiness of the scant research backing his first term agenda.
One issue is just trying to keep some perspective on the nature of a claim about benefits spread over the life of a child. Saying a $19,000 investment in high-quality pre-school can save the government seven times that over the life of a child is not that dramatic. If the government put $20,000 in a savings account paying 5% interest, 40 years later they'd have $140,000 (at least according to this thing).
Or, put another way, if you divide $140,000 over 40 years, you're talking about $3,500 a year per person in increased tax income, and especially decreased public services. If you have two kids who qualify for free lunch, you're talking $1000 of government expense right there per year for 13 years. If pre-school helps bump you clear of poverty -- even if you didn't go to college -- the dollars add up quickly.Obviously keeping one person out of the 0.7% of our population that we imprison pays for many, many others who see no measurable effect.
Also, the studies this x7 number comes from are from actual observation of the life outcomes of students over 40 years. Even though the samples are small, I'll take that over the bullshit extrapolations of a couple years of test scores we've been handed lately.
Finally, pointing out that this only works with quality child care which we can't afford misses the whole point, which is you really can afford the more expensive child care because it is a good investment.