Cover: Students Using Lexia® Core5® Reading Show Greater Reading Gains Than Matched Comparison Students

Students Using Lexia® Core5® Reading Show Greater Reading Gains Than Matched Comparison Students

Published Sep 6, 2023

by John F. Pane, Dorothy Seaman, Christopher Joseph Doss

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Research Questions

  1. How do reading achievement gains of students who used Core5 compare with those of a matched comparison group of students who did not use Core5 during the 2021–2022 academic year?
  2. How do estimated effects of Core5 vary for subgroups of students based on grade, gender, race/ethnicity, or baseline levels of achievement?
  3. How do estimated effects of Core5 vary depending on whether students met usage targets set by the program?

This report evaluates the effects of Lexia® Core5® Reading (Core5) — a product of Lexia Learning Systems — on the reading achievement of students in grades 3–5 during the 2021–2022 academic year. Core5 is a program that focuses on various student literacy skills, such as fluency, vocabulary, and comprehension. This report represents the first study in a broader effort to develop independent and rigorous research evidence about the effects of Core5 on student achievement.

The authors compared the performance of students in a school district that used Core5 with similar students in similar schools across the United States that did not use Core5. The analyses estimated that students who used Core5 experienced larger reading achievement gains, on average, than their counterparts in the matched comparison group. Differences in outcomes measured in this study are likely to have been caused by Core5 use, but the methods used cannot unambiguously rule out selection bias to establish that causality. Moreover, study results might not generalize to all grades in which Core5 is offered or to all U.S. schools.

Key Findings

Core5 students and all examined subgroups outperformed their comparison group counterparts

  • The standardized effect size of about 0.11 is equivalent to having about 54 percent of Core5 students outperform the comparison group median on the spring 2022 reading assessment.
  • Core5 results by grade level and by gender closely track the overall Core5 estimate. When examining race/ethnicity subgroups, White students are estimated to have experienced gains of 0.15 relative to the comparison group, whereas Black and Hispanic students experienced gains of 0.05 and 0.06, respectively.

Core5 students who met usage targets experienced larger gains than students who did not

  • High-usage students outperformed their comparison group peers by 0.16 on the standardized effect scale, which translates to 56 percent of such students surpassing the median of their comparison group counterparts.
  • By contrast, Core5 students who were not in the high-usage subgroup were estimated to experience effects of only 0.06.

Core5 students also made gains relative to national norms

  • Students in grade 3 began the 2021–2022 academic year performing significantly below national norms, but, by the following spring, they were performing significantly above national norms.
  • Students in grades 4 and 5 started the year already performing above norms but also experienced gains during the study period.
  • In all three grades, the comparison group experienced smaller gains or losses relative to national norms.

Research conducted by

The research described in this report was sponsored by Lexia Learning Systems, LLC and conducted by RAND Education and Labor.

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