Sure there are differences overall. In talking with other parents, for instance, the privates around us have classes on ways to study methods (notetaking, how to approach tests, things like that). Our public school does not do this (nor does any of the public middle schools we looked at). The privates around us also seem to give a lot more homework (even during the summer break).
Our math programs seem average for what they are learning. We have been going to additional math tutoring outside to get our son ahead but it wasn't because of the program at his school (we started in Kindergarten).
There is a also lot of info around bullying and so on. I just figured this was all schools. This one I don't know about at the other schools around us.