Wiki - John Taylor Gatto also has some info about him.
He promotes homeschooling, and specifically unschooling. One professor of education has called his books "scathing" and "one-sided and hyperbolic, [but] not inaccurate."
Btw efforts are now being made to completely disallow homeschooling of any sort in United States. I know I may sound lunatic if I say it is just a matter of time homeschooling will be banned in most of the countries in the near future, but I will say it anyway, because I think this is the direction we are now heading. Take from it what you will -
Homeschooling Banned in California as State Turns Parents Into Criminals for Teaching Their Own Children
and more bollocks -
Home education 'can be cover for abuse and forced marriage'