In Michigan, Larry Schweinhart is an early childhood program researcher at the nonprofit education research organization HighScope.

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The 123 African-American students were split randomly between those assigned to the HighScope Perry Preschool Program and those who weren't.

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So I went to the next best thing -- two women who attended a HighScope preschool in Michigan but weren't part of the studies the group ran.

CNN: Does pre-K work? Ask old people