I have been following with interest the comments section of the recent New York Times article  on the "cupcake wars," which explores the tensions among PTA parents in neighborhoods that are gentrifying.
A number of the comments are alienating in that they seem to embrace competitiveness and divisiveness among parents of differing backgrounds and means. But I think there is an even more disturbing issue here.
Free public education was supposed to level at least the initial academic field, providing the children of impoverished parents with the same chances as the children of the rich to get into a good college and pursue their vocation of choice. (Paying for college is, of course, another matter, as Aeron points out in this week's excellent post.)
It doesn't work out that way, though. I have worked in public schools where there virtually was no PTA. In some schools this was because the parents worked at multiple low-wage jobs to pay their rent and keep the kids clothed and fed. At others, many parents had succumbed to addiction and despair.
There were no "cupcake wars" at these schools, because there were no fundraisers. The kids made do with outdated textbooks, and in one school the minuscule "library," consisting of random books donated by teachers, was closed because there was no one to supervise it.
Many of those kids aspired to be doctors and schoolteachers, but because they were crammed into overcrowded classrooms with insufficient teacher attention and teaching materials, even some of the brightest could barely read when they graduated from the fifth grade.
There were no parent volunteers monitoring the halls, the lunchrooms, or the stairwells, and bullying was rampant. Gang members recruited runners in the schoolyard, and there was no one to drive them off.
My son attends a public school, but it is a "good" one, which only the more savvy parents even know to apply to. Parental involvement is high. Parents and kids collaborate to raise funds and to devise creative ways to stretch them as far as possible. We have sent the band to France and to England to perform, we sponsor educational and recreational field trips, and we make sure every classroom has adequate supplies. It is not a rich school, but every student is getting a rich education.
These advantages shouldn't be dependent on the means and commitment of the parents. Aeron makes the point that skyrocketing tuition is likely to create a "caste-based system of higher education, where only the children of the very wealthy have options." If we don't fund primary and secondary schools equally and properly, students from less affluent areas won't even develop the skills to apply to the "top" colleges, or any colleges, let alone pay their tuition. And we are all poorer for that.