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Updated: May 25, 2026
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A Tablet-Based Curriculum-Based Measurement Protocol for Kindergarten Writing
Published on: February 7, 2025
How does your kindergarten classroom affect your earnings? Evidence from Project Star
Raj Chetty1, John N Friedman, Nathaniel Hilger
1Harvard University and National Bureau of Economic Research.
The Quarterly Journal of Economics
|January 19, 2012
Summary
Small class sizes and experienced teachers in early grades significantly boost college attendance and other long-term outcomes. Early education quality, even beyond test scores, impacts future success.
Area of Science:
- Education
- Economics
- Sociology
Background:
- Project STAR randomly assigned 11,571 students to classrooms from kindergarten to third grade.
- Kindergarten test scores predict long-term outcomes like earnings and college attendance.
Observation:
- Linking experimental data to administrative records reveals long-term impacts.
- Small class sizes correlate with higher college attendance and improved outcomes.
- Experienced teachers in kindergarten are linked to increased earnings.
Findings:
- Students in higher-quality K-3 classrooms show better earnings, college attendance, and other life outcomes.
- Class quality effects persist in noncognitive measures, though fade in test scores.
- Class size impacts college attendance but not significantly earnings at age 27.
Implications:
- Early education investments, particularly in class size and teacher experience, yield significant long-term benefits.
- Classroom peer effects and teacher quality are crucial for student development.
- Noncognitive skills developed in early education have lasting positive effects.
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