In general, I seem to agree with libertarians more than other political views, although I'd call myself an "open source libertarian" rather than a "free software libertarian". For non-geeks, (or geeks of a different stripe) that means I'm not wedded to the ideals in their pure form, but rather believe that in most cases those ideas will have the best results.
Public infrastructure is a legitimate place for government. I think at least K-12 education is in a sense infrastructure--it is the basic core that aids progress and helps avoid tyranny. Education promotes commerce, educated soldiers are better able to defend our country. I don't think this translates to an individual right to education. Rather, it is good policy to spend education dollars as efficiently as possible, with several goals.
The first goal is to get the majority of the population to a reasonable level of education. Literacy, history, math (with a lot more practical applications--I'll do another post on that a bit later) government--How it works, and how to be involved to influence it. I think sports is over-emphasized. We worry too much about sports in school--It may benefit individuals, but I don't think sports programs benefit society. I may be biased, because I'm not an athelete and was never involved in school sports.
The second goal should be to identify Talent, and nurture it. This isn't for the benefit of Talent, but rather for the benefit of the rest of us--The more Talented people we have working on our problems, the quicker those problems will be solved.
Another reason that K-12 education is different is that kids shouldn't be held to the same standards as adults, and shouldn't be punished more than necessary for their parent's failures. By the time you can be responsible for yourself, it is essentially too late to catch up, regardless of talent or effort. I don't want generations of uneducated people, especially clustered together where the kids don't get to see the benefits.
I see some of the pitfalls of public education. I deplore most of the zero tolerance rules. It is an immense mistake to make self-defense a zero-tolerance offense, especially in cases where the truth is reasonably deciphered. I don't think it is intentional, but the result is teaching that authority is responsible for everything, don't be self-reliant.
I don't know what level of government should be responsible for education. Federal has an interest, but I don't know if it is enough to justify federal involvement in most cases. On the other hand, there are problems with education being funded entirely locally--There are cases of poor areas spending a higher percentage of total income on education, and still not having enough.