What's the best age to start enrichment classes??

The more important question to ask is: "Is your child ready to learn?" Sometimes it's not about age but about where your child is in terms of development. Be sure to be on the lookout for social, cognitive, and (in some cases) physical signs that can indicate when your child is ready for school. In any case, an appropriate ball park estimation for a child's first enrollment could be anywhere from 4 to 5 years old. source: http://www.babycenter.com/0_kindergarten-readiness-is-your-child-ready-for-school_67232.bc