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
  • Two studies were conducted to measure the effectiveness of the CommonLit 360 Curriculum.
    • A Case Study of CommonLit 360 in Blount County illustrates how one district in Tennessee went from among the lowest performance categories to the highest following implementation of CommonLit 360. Interviews with school and district leaders provide a window into the factors that led to these dramatic gains.
    • A Study of CommonLit 360 in NYC Schools illustrates the reading achievement results of seven high need middle schools in New York City. The results showed statistically significant gains in reading achievement, across all grades. Fidelity to the program was a predictor of better outcomes, with demographic subgroups showing improvement on par with their peers.
  • 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.