More on Economic Diversity

So I have been reading a lot about the benefits of economic integration lately, and I came across this chart from an article called Raleigh: a Model for Economic School Integration by Alan Gottlieb in the May 2002 issue of The Term Paper from the Piton Foundation.

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The whole issue of the Term Paper argues that economic integration is a benefit for everyone involved, this chart (on page 5) is used to document the improvement of subsidized students who attend majority middle class schools, but doesn't it also show that there is an even more significant penalty for middle class students who attend predominantly low SES schools?