This. When I graduated high school (about 15 years ago) the amount spent per student was around $5k a year. The high school was in the top 1-2% of public schools nationwide. The school now spends around $14k per student and is in the top 15-20%. What changed? The perception of the school. The parents whose children would pull that number up have chosen neighboring school districts (myself included).
The urban schools actually get the most per student in the state. $14k-$15k from the district alone, with additional state funding pushing that number north of $20k (some schools reaching $25k). There is not a funding issue at all. They have the lowest student to teacher ratios in the state, along with the most teacher aides and social workers.
And this isn't on the coasts, this is in the upper midwest, so the cost of living is not high.
For instance, a starting teacher's salary in Michigan is around $30,000-35,000 a year. I know I personally wouldn't want to work, for that low of a salary, for 60+ hours a week (managing and teaching classes of 25+ students for 8+ hours a day, then having to use time outside of class to plan further lessons, manage paperwork, work on professional development, do all of the other crap required by school administration), for 9 months out of the year with some ad hoc work during the summer "vacation". I especially wouldn't do all of that just for everyone to tell me that I'm doing it wrong (which seems to be the major public opinion currently), and I have a feeling many people who would be great educators are smart enough to realize it isn't worth it for these same reasons.
I don't deny that there are things of value that are hard to quantify with precision. That doesn't mean they can't be measured at all. For something to be of value, it must have detectable consequences, at least statistically or eventually. The detection of its consequence is a measurement, and that consequence, even if roughly measured, can be compared to the cost to achieve it. If it has no detectable consequences at all, though, it is not worth paying for.
If the schools tell you that they are teaching "critical thinking", for example, ask them for a demonstration of something a child can now do that he couldn't before his critical thinking instruction. If they can come up with something, they've figured out a way to measure it; if not, it's either just a meaningless buzzword or they don't know enough about critical thinking to be paid to teach it.
When they tell you that your past increases to their pay have produced no measurable improvements but lots of unmeasurable improvements, tell them that until they can find a way to measure those improvements, their future compensation increases will be in the form of unmeasurable benefits.
Obviously no test is perfectly an aptitude test, and the easiest way to raise average SAT scores is to teach strategies specifically for the SAT.
And even the SAT depends on how big your vocabulary is (comes from extensive reading of challenging material that is no longer fashionable at elite campus schools of education), how fluent you are in the math they use (fluency comes from what "progressive educators" ridicule as "drill and kill"), and so on, which is why the College Board had to "recenter" the scoring in 1995 after three decades of decreases in educational "aptitude".
Schools take on a lot of roles that really should be handled by social services.
I wonder how much is spent directly on education.
So, if giving the schools a lot more money bought no better educational results, then continuing year after year to increase funding beyond inflation, spending more than any educationally superior country, still left educational outcomes essentially unchanged, what are the chances that the major problem is the level of funding?
Isn't it a lot more likely that the major problem is what the school systems actually do? If they could show that each 10% increase in funding in a given location had produced an average 40 point gain in SAT scores, I would want to talk about further funding increases in that location. On the other hand, if they showed that each 10% increase in funding produced, well, 10% more for the staff but nothing for the students, I would want to discuss changes other than funding.