My children never attended preK but knew much more than the average Kindergartener - going to preK does not mean they will know more/or less than others. Parenting will determine what they know when entering Kindergarten - not schooling necessarily. My daughter was reading at 3 at a first grade level... She knew ABC's by the time she was 18 months old, said her first word at five months and could talk in complete sensible sentences when she was one year old. Granted my boys were not at the same level at the same ages, but they did know as much as, if not more, than the average beginning Kindergartener when the time came.