Your first step is an easy one -- find out when the kindergarten cutoff birthday is in your state/school district (MA?). Here in NC, it is October 15 for this last year -- it moves to September 1 next year. If you lived in NC, you couldn't send your child to kindergarten w/o requesting and being approved for a waiver. This is the trend -- start dates are being moved up. I don't want to generalize too much, but I would wager that in some regions the majority of parents would not send a November birthday child to kindergarten until the following year (two to three months prior to their sixth birthday).

Many, many children attend some sort of organized schooling when they are four years old (many even earlier than that). This is traditionally called "pre-kindergarten" or "preK." Answering this question is timely for me, as my four year old son will spend his last day in his preK class tomorrow. I'm pulling him for six months straight at home, trips to the zoo, museums, etc.. His preK graduation date was 5/15 anyway, so we're really just pulling him out 10 weeks or so early. I have a good friend who did not preK or preschool his daughter -- she stayed w/ her grandmother while both parents worked. She's doing very well in school -- now in the first grade. PreK is very popular and I would argue should be viewed as preferable for a four year old, but I do not think it is necessary for everyone.

PreK is generally private. It's run by private companies, churches, private schools, etc.. Many school systems do offer free public preK, however (often under monikers like "Head Start").

Honestly, walk into the elementary school in your neighborhood or the central office of your local school system and plead ignorance. Say you don't have a clue as to where to start re: preK (free, public or private), kindergarten readiness, etc.. I bet they'll help you a great deal.

I Colorado, I believe it is five by Sept. 15 and I think in general terms it’s 5 in most states; we missed the cutoff age/date by mere weeks this last fall. However, check your school district web site for the dates, they are there; and they all too often have a pre K preschool in the public school. It is cheaper than, and not as long as a commercial preschool but better. It gets their name into the system, they go to preschool with the kids the will be going to school with; and it gets you familiar with the school layout, calendar, staff and policies, and you can start doing celebratory back flips a year earlier.
As a matter of fact, just last night I went to the 1st of many Kindergarten meeting because my kids graduates from the preschool ranks to ¾ day preschool in the fall.
I have done the high dollar commercial preschools and the public school preschools, and the public school system is by far the better deal for both of us.

-Mike My Site, http://www.milehidad.com/ and my Blog, http://www.milehighdad.net/.
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Thanks for everyones input here. i was having the same question

Registration for the next school year is coming up soon here in Plainfield Ill. I dont know about when the start in Boston. Also the cutoff date is around sept1. So now is the time to contact your school district to find out. Also the age for kindergarden is 5. Preschool for 3 and 4 year olds registration usually is in January, and out here if you missed it your out of luck. Even the priviate pk schools are all booked up. We were fortunate when we moved out here to find a priviate pk school at a local church that had a policy once one goes there all the rest can go without having to go through the lottery system again. Hope this helps.
Also they had to be potty trained before the start of the school. We ended up sending one of the kids who had turned 3 in Aug with a pullup on the first day.

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