It's also true in Ontario (Canada) that school is not required until grade one, and if your child was born between September and December, they have the option of waiting an additional year to start school in grade one.
I disagree, by the way, that children miss out on a lot by not attending pre-kindergarten. There is no research to show any long-term benefits except to children from low-income, deprived homes. The only difference is that the kids who have been in these JK/SK programs learn the school routines, but six-year-olds starting in grade one will pick those up pretty quickly.
It does make sense for parents who would have their children in daycare situations otherwise - it's certainly helpful to them to have a taxpayer-supported, educational program. But a parent at home with young children can provide plenty of opportunities for learning, creative play, outings in the community, etc.
Teresa Pitman