“How much do students here learn? How do you know?”

These questions posed by David Brooks in an article in the NY Times are symptomatic of the need to assess education, but Brooks is missing the point when tries to use some pseudo  quantitative information related to the "amounts" learned by students in college.
This misguided attempt to measure gain is skills using Arum and Roksa's study “Academically Adrift", where they "found that, on average, students experienced a pathetic seven percentile point gain in skills during their first two years in college and a marginal gain in the two years after that." But then Brooks mention that the numbers are "disputed" and continues by saying "but the study suggests that nearly half the students showed no significant gain in critical thinking, complex reasoning and writing skills during their first two years in college." So why use the suggestion of the study if the numbers are contested?
There are other ways of knowing how education is affecting one's life and ways to quantify the benefit of higher education for instance the average income of tax payers with or without a four-year college education. The percent of unemployed with or without a college degree and so on. So when Brooks ask parents to ask the question to college administrators "How much do students here learn?" is misguiding them as a more appropriate question would be: How do you assess the quality of the education provided here?
This question will make parents more involved in their children's education and will also help them to see the need of hard work and commitment when choosing a career more so today when STEM majors are lagging way behind other industrialized nations.