lesschumras, joint operation is nice, but brings up other issues.
Who do you allow to join this venture? Is it any Jewish school? Does that include reform and conservative? If no, where does the line get drawn? Some people on this site don’t think MO fits into the orthodox category, so its a very touchy subject.
Otherwise, I think many people underestimate the cost of running a school. The electric/gas/oil bills alone are substantial. Teachers are also vastly underpaid, so we really need to pay them better. What is more important than making sure our kids have a strong Jewish foundation? Yes it begins at home, but school is extremely important.
Honestly, I think if Jews got together, we could also form a group for health insurance. With so many orthodox Jews in the NY area alone, we would qualify for large corporation discounts. It would require membership somewhere (maybe the OU? They are a fairly neutral company) but would allow lower cost health insurance for much better rates then most people have access to.