Preschool Works.

Preschool makes huge differences in how well you succeed in life, at least if you are starting out at the bottom of the socio-economic pyramid. According to the source cited in the link above:

By age 24, children who had participated in the Child-Parent Center preschool were:

* More likely to have finished high school (71.4 percent vs. 63.7 percent) and to be attending four-year colleges (14.7 percent vs. 10 percent)
* More likely to have health insurance coverage (70.2 percent vs. 61.5 percent)
* Less likely to be arrested for a felony (16.5 percent vs. 21.1 percent) or incarcerated (20.6 percent vs. 25.6 percent)
* Less likely to have depressive symptoms (12.8 percent vs. 17.4 percent)
* Children who participated in the program during preschool and early school years also were more likely to be working full-time (42.7 percent vs. 36.4 percent), have completed more years of education and have lower rates of arrests for violent offenses (13.9 percent vs. 17.9 percent), and were less likely to receive disability assistance (4.4 percent vs. 7 percent).

These differences were still measurable two decades after the pre-school program.