During children's typical 12-year stint in the public school system, the most "successful" learn not to question authority, not to ask questions which don't pertain to the task at hand, to follow procedure, to be a team player, and not to stand out.
Children are trained to sit still for increasingly longer time spans while doing mentally menial busywork - and punished if they are unable or unwilling to. During recess children learn the importance of being well-liked and fitting in--that is, being unique and special within a certain restricted range. These are the essentials for later success on the job.
The mass education in high schools reflect mass production of the workforce. The teaching style has one teacher (supervisor) lecturing (leading) 20-25 students (workers) sitting in rows, much like a manager and his employees. Practically all problems that are presented are closed-form problems where there's only one answer that, by construction, can be found using the methods in the textbook. The subjects taught are selected to be testable, preferably using standardized exams with predefined answers. This means that most subjects are mechanical rather than organic in nature, in the sense that they have a well-defined problem with an easy, step-by-step method of arriving at a solution, rather than an open-ended problem with nonlinear and complex solutions.
This means is therefore an advantage to focusing on memorizing the textbook rather than attaining a broader understanding. This is excellent training for intelligently following procedure, but also a powerful counter-training against using intelligence creatively.
This kind of education doesn't instill much permanent information, and it doesn't require much deep understanding of the fundamentals. It doesn't instill knowledge and it certainly doesn't instill wisdom. What it mostly does is to test the students' short-term memorization skills, and their willingness to use these talents to maximize their test scores and grades.
Typically, after high school, students are encouraged to go to college. A college degree has come to serve as an admission ticket to the white-collar job market, as employers deemed that the selective process of getting through a college education is perfect for selecting the most mentally disciplined workers. Salaried, white-collar jobs are desirable because they're thought to provide superior and stable pay and fringe benefits. They're also less strenuous and less dangerous than manual labor.
Colleges and universities have responded by lowering academic standards and raising their prices, much like other producers of consumer goods and services respond to rising demand. This has resulted in an overabundance of college-educated people with useless degrees. This creates structural unemployment, which is generally bad for society, bad for the unemployed, but good for employers. Students get their degrees, and everybody is happy--except those that came to learn and be challenged, and in many cases went deep into debt for the privilege.
These years spent institutionalized1, could alternatively be spent developing creativity, spending time with family, and learning about themselves and the world around them. Rather than enriching our children, these systems serve instead to prepare them for the workforce.