The challenge
No one knew if smaller classes really improved learning for young children.
The case
From 1985 to 1989, Tennessee randomly assigned about 11,600 kindergarten-to-third-grade students and their teachers to small classes of 13–17 pupils or regular classes of 22–25. Children in small classes scored higher on tests, with the largest gains for Black students and children from low-income families. Later research linked small-class assignment to higher college attendance.
Why it worked
STAR showed smaller classes can help young children, especially disadvantaged ones. When California cut class sizes statewide in 1996, results were weaker, partly because it had to hire many inexperienced teachers quickly.
Sources
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