No, it doesn't have anything to do w/ Harry Potter. It's an awesome rant about how crappily mathematics is taught in school, about how the education system ruins education. Here's the PDF. The intro, to whet your appetite:

A musician wakes from a terrible nightmare. In his dream he finds himself in a society where music education has been made mandatory. “We are helping our students become more competitive in an increasingly sound-filled world.” Educators, school systems, and the state are put in charge of this vital project. Studies are commissioned, committees are formed, and decisions are made— all without the advice or participation of a single working musician or
composer.

Since musicians are known to set down their ideas in the form of sheet music, these curious black dots and lines must constitute the “language of music.” It is imperative that students become fluent in this language if they are to attain any degree of musical competence; indeed, it would be ludicrous to expect a child to sing a song or play an instrument without having a thorough grounding in music notation and theory. Playing and listening to music, let alone composing an original piece, are considered very advanced topics and are generally put off until college, and more often graduate school.

As for the primary and secondary schools, their mission is to train students to use this language— to jiggle symbols around according to a fixed set of rules: “Music class is where we take out our staff paper, our teacher puts some notes on the board, and we copy them or transpose them into a different key. We have to make sure to get the clefs and key signatures right, and our teacher is very picky about making sure we fill in our quarter-notes completely. One time we had a chromatic scale problem and I did it right, but the teacher gave me no credit because I had the stems pointing the wrong way.”

In their wisdom, educators soon realize that even very young children can be given this kind of musical instruction. In fact it is considered quite shameful if one’s third-grader hasn’t completely memorized his circle of fifths. “I’ll have to get my son a music tutor. He simply won’t apply himself to his music homework. He says it’s boring. He just sits there staring out the window, humming tunes to himself and making up silly songs.”

I once read a paper that looked at the correlations by country of spending on public education to see if public education tended to go with democracy or wealth. It actually turned out that the highest correlation was with state control of the media. In other words, public education systems are the largest in despotic countries - which makes sense to a crazy libertarian like myself.

The story of Melissa Busekros in Germany is a vivid anecdotal demonstration of the theory. Melissa was being tutored at home in subjects she was behind at in school. When the school found out, she was expelled (because homeschooling is illegal in Germany), evaluated by a psychiatrist, diagnosed with "school phobia", and involuntarily committed to a psychiatric ward. All for liking learning at home. Other children are picked up from home and taken to school by police officers in order to make sure they attend.

Fortunately it was not long before she turned 16, which gave her the right to leave psychiatric custody.

Germany's attorney general gives the reasons for this policy:

Wolfgang Drautz, consul general for the Federal Republic of Germany, has commented on the issue on a blog, noting the government "has a legitimate interest in countering the rise of parallel societies that are based on religion or motivated by different world views and in integrating minorities into the population as a whole."

Drautz said homeschool students' test results may be as good as for those in school, but "school teaches not only knowledge but also social conduct, encourages dialogue among people of different beliefs and cultures, and helps students to become responsible citizens."

As a zealous atheist, I find it said that so many kids in the US are brainwashed by conservative Christian parents as part of being homeschooled. But I still see that as much less dangerous than having everyone brainwashed by the state. If kids are going to be brainwashed by someone, I trust the parents more, and anyway I favor diversity of indoctrination to a monoculture.

Looks like yet another example of overreaction to the Holocaust causing stupid German policies.