Seems like kids are starting puberty earlier and entering adulthood later. My grandmother was married on Christmas Eve by 20 and was raising a baby and working full-time shortly thereafter. She grew up during the Depression and worked a job as soon as she could to help support her family. My grandfather was off fighting in World War II (can't grow up much faster than fighting a war) and then came back to a job that he worked very nearly until retirement, raising three kids with his wife. My parents were the same way, and I had my first job at 15, the earliest I could get one, craving both spending money and independence.
These days, the biological age at which kids begin their sexual development (puberty) is getting lower and lower while the entrance into the "normal" occupations of adulthood is coming later and later; in 2008, the College Board reported that only 57% of enrolled college students would finish their degree within six years, and young adults are delaying marriage and childbearing at historic rates as well (median age at first marriage chart here).
What happens when children reach puberty earlier and adulthood later? The answer is: a good deal of teenage weirdness. Fortunately, developmental psychologists and neuroscientists are starting to explain the foundations of that weirdness.
Bringing them "into sync" is crucial, both for their health and happiness. If the first system deals with reward (primarily social rewards from peers for teens) and the second deals with control (learning not to make the same mistakes over and over again), then adolescents need lots of opportunities to be successful and brilliant (ideally in front of an appreciative, supportive peer group) and to fail (ideally in front of a supportive, instructive adult or mentor who can help them work through their mistakes and learn to avoid them in the future).
In the distant (and even the not-so-distant) historical past, these systems of motivation and control were largely in sync. In gatherer-hunter and farming societies, childhood education involves formal and informal apprenticeship. Children have lots of chances to practice the skills that they need to accomplish their goals as adults, and so to become expert planners and actors.
In the past, to become a good gatherer or hunter, cook or caregiver, you would actually practice gathering, hunting, cooking and taking care of children all through middle childhood and early adolescence—tuning up just the prefrontal wiring you'd need as an adult. But you'd do all that under expert adult supervision and in the protected world of childhood, where the impact of your inevitable failures would be blunted. When the motivational juice of puberty arrived, you'd be ready to go after the real rewards, in the world outside, with new intensity and exuberance, but you'd also have the skill and control to do it effectively and reasonably safely.
Our current system of education does not encourage these types of practice in the skills that adolescents need to survive today.
The experience of trying to achieve a real goal in real time in the real world is increasingly delayed, and the growth of the control system depends on just those experiences.
This results in young adults who cannot move out of their parents' basements because they lack the skills and confidence to truly manage their own life and experiences. The article under discussion points out that kids today are not "stupider" and are, in fact, much smarter and more savvy in many ways. Still, without the practice of skills and independence, the accountability and correction of failure and the encouragement of peers and involved adults, we are winding up with young adults who "develop and accelerator long before they develop a brake."
Adolescents need opportunities for practice, for success and failure, for specialization in something they love and for building life skills, starting in pre-adolescence and continuing until they are on their way into the world. This is not how our current system of education is structured, and it is not how it is currently being "reformed." Ask yourself this: what are the chances of success in education if it ignores the way our brains develop?