CommonLit has proven to be an effective, engaging, research-based reading program.

  • Based on analysis of over one million students using CommonLit during 2017 and 2018, a third-party evaluator authored a report on CommonLit's effectiveness. The report found that:
    • Students who complete more CommonLit assignments experience greater gains in reading performance
    • Increased CommonLit usage is associated with more students at proficient or mastery level on a state assessment
    • Students at Title I (low-income) schools experience greater gains on CommonLit
  • A study of the CommonLit 360 Curriculum in seven middle schools in New York City showed statistically significant gains in reading achievement, across all grades. Fidelity to the program was a predictor of better outcomes.
  • Students who were exposed to CommonLit in our 2014 quasi-experiment showed greater gains in student engagement than a comparison group. Read our full report from 2014.
  • CommonLit is entirely research based. Our whole program is designed to nudge teachers to use best practices in adolescent literacy instruction. Learn more about the practices CommonLit promotes here.
  • CommonLit released an open-source corpus of 4,700 reading passages tagged with difficulty. The 2021 CLEAR Corpus was used to develop a new readability algorithm and is now available to researchers free of charge.