Here are links to two articles written by Anne Wheelock, Damian J. Bebell, and Walt Haney. These articles discuss the effects the MCAS has on students from different background. The articles are particularly interesting in their inclusion of numerous pictures drawn by kids.
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http://www.tcrecord.org/Content.asp?ContentID=10635
http://www.tcrecord.org/Content.asp?ContentID=10634