Thanks Stan. I tried to move closer, to the sides of the rows, but the every other parent had the same idea and the school decided that you can only shoot seating from your assigned row.
Spending too much is really not in my plans. I was ready to upgrade my D90, and than I realized that a D7000+ a 3rd party 70-200 2.8 would cost more or less the same of a D600. Therefore, if the image quality of a D600 at iso 3200 and 300mm 5.6 using a 70-300 VC were to be better than that of a D7000 at iso 800 and 200mm 2.8 (assuming those are equivalent exposures), it could be a better value proposition. But, that assumes that the D600 at 3200 has an IQ that is better that of the D7000 at 800.
That is my dillema. But the info so far have open my mind to think about the trade-offs and options.