KnightMOM,
I'm not sure of what you're meaning regards old & new communities. Have the school lines been redrawn and you now have lower income students along with higher income? Language differences? Or has a new development been built among the older homes? All schools have students coming in & out all the time--PTO is for the school as a whole, not one particular portion of it, so I'm not understanding what the problem is that you're having. Sorry I'm not much help. Maybe if you can give a for instance.
Our elementary school is split between the "old" community and a "newer" community. The older community is resentful of any change and trying to bridge the two cultures is difficult especially when trying to have unity in the PTO.
I would like to hear from other PTO members that have experienced this situation and what they did to improve the situation.