Well, you will probably know when the school events are going to be photographed. In that case, maybe you should go for the 24-70 F/2.8 now and just rent the 70-200 when you need it. Keep an eye on CL because the occassional 80-200 F/2.8 AF-S do show up for $1000 to $1200 (made for a few years, disco'd in 2004 I think.) It has AF-S but not VR, which is why it gets cheaper.
My next lens will be the 70-200 F/2.8 because of the shooting I will be doing. But I'd love to get the 14-24, 24-70 and 70-200 plus a 1.4x telecon and eventually dump the 18-200. It is a great lens, but not nearly fast enough for the shooting I find myself doing (indoors and lower light.....) Just need to win the lottery (or rob a bank) to pay for it....
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Scott
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