In the 1960s John Holt, a former teacher, wrote a couple books about the failing school systems. In these books, he identifies some real problems about many schools. He comes to one conclusion, that schools always fail because teaching is accomplished through external motivation rather than internal motivation.
Holt notes that many children fail at school because they in part because fear getting the wrong answer or become dependent on the praise of the teacher, focusing learning on what the teacher wants rather than on the nature of objective reality.
In the words of Holt:
Since we can’t know what knowledge will be most needed in the future, it is senseless to try to teach it in advance. Instead, we should try to turn out people who love learning so much and learn so well that they will be able to learn whatever needs to be learned.
If this is the basis of Unschooling, then I disagree. Not the love of learning part, but the part about knowing what knowledge will be most needed in the future. There most certainly are subjects that will necessarily be important for all individuals in the future, some to a greater extent than others. But all necessary. Reading, writing, math, history... all necessary subjects for any career. One could make the argument that 100 years ago, those subjects were not necessary for some careers such as farming or manual labor jobs. But with advancing technology requiring ever more sophisticated knowledge, developing basic knowledge is absolutely essential.
Unschooling fails to fully address why external motivation is inherently wrong in motivation. Holt focuses on rewards and punishments, but wrongly includes persuasive motivation as a bad type of external motivation.
Take for instance Michael Phelps (the American swimmer striving for a historic 8 Olympic gold medals while I write this). His mom first sent him to swim lessons as an outlet for his energy. Michael did not have internal motivation to take up swimming. His mom encouraged him, persuaded him, to try it out. Once his skills were identified by his swimming coach (when he was 11), he first approached Michael's mom about the possibility of becoming an Olympian. Once he convinced her, they persuaded Michael to do the same. Sure, it was easy to persuade an 11 year old to shot for the gold, its an easy dream to latch on to. But it was external to his motivations.
While I believe unschooling ultimately fails as the ideal educational method, I can understand its appeal to Objectivists. The appeal to personal goals driving education strikes at the individualist heart. However, to hope a child will blindly find their way through self-development, is, in my opinion, naive. After many years of schooling, I understand that learning a new subject on my own is highly inefficient. I could follow many blind alleys before I truly understood a subject. By using a structured educational program, I can rapidly learn subjects. Using persuasive motivation to convince our kids of this importance is entirely justified.