P.M.
I hope you'll google "the importance of play in early childhood," because all the most recent evidence points to this as being the single most essential means for children to develop emotionally, socially, AND academically.
While it's admirable and probably helpful to expose our children to a wide range of stimuli, we can also run the risk of overstimulating them, or distracting them from their real "work," which is play! One thing we can do for small children is to talk to them. And read to them. A large vocabulary is the single strongest predictor of a child's success in school.
Too much stress on academic learning in the early years actually backfires. Kids can enter school feeling little joy in learning, too much pressure, and little ownership of the process if they are trying to meet their parents' expectations.