Hopefully, this isn't too self-aggrandizing, but I wanted to share an article I read this week about the value of early childhood education. As Montessori observed, it is true that the most important years in a child's life may not be those of university studies, but the formative years (when a child's brain is literally wiring itself up, learning how to store and retrieve information efficiently, and learning how to learn).
What is the value of a good kindergarten experience? Well, according to Harvard economists, about $320,000 in earnings before the age of 30 (in addition to social gains like improved physical health and lower crime rates)! Pretty staggering!
(and, oh, lower class sizes- like 13-17 vs. 22-25, apparently that helps too!)
Here's the article from the New York Times: http://www.nytimes.com/2010/07/28/business/economy/28leonhardt.html