Unless you are driving an ice cream truck through the neighborhood its hard to tell. I advise my clients to drive through in the morning on school days to see the children at the bus stop. It will give you a feel. I always ask the next door neighbor at a showing (if I see them out) if there are any kids around. The best memories of my childhood are playing with the kids who also lived on the street. It is a very important issue when buying a house.
Most Westford neighborhoods have a good mix of ages. I would suggest knocking on a couple of doors to inqire about how many children are in the neighborhood. We know at least three families with children who live there. Here is their community website: