Today's preschools are more than just naps and graham crackers, swing sets and "Baby Beluga".
As a kid I went to a private Christian centered pre-school because my grandmother's best friend worked at the school and I was able to go there for free. I believe the school provided me with social opportunities and a curiosity for religion that has never left me. At the time, my parents had just had one of my younger sisters so going to pre-school was a great way for me to interact with peers and to integrate my outgoing and leader type personality with lots of different kids.
As a college student, I worked at a pre-school during my summers off. I had the chance to work with white and Asian kids who were mostly from a middle socioeconomic background. The school integrated child and teacher centered activities, lots of physical play, and an emphasis on life skills such as cooperation, individuality and specific skills like potty training, tying shoes, reading- through Zoo Phonics, etc.
I do not have children, but I do believe that pre-school is essential to modern society and the growth and success of children, While many types of pre-schools are beneficial for children, schools with a constructivist approach develop independent, curious, social children. Kids need to learn to make decisions and to be confident in who they are. Furthermore, pre-school is one of the only types of school settings that allow kids freedom and choice. I believe that kids need to have these types of opportunities before they enter the more rigorous, behaviorist centered American school system.