Study: Knowledge-Rich Curriculum Significantly Boosts Reading Scores
The long-term effects of the Core Knowledge curriculum saw students’ reading scores improve by 16 percentile points on state standardized tests.
The results of a long-term study conducted by University of Virginia researchers show that the Core Knowledge curriculum improved students’ cumulative, long-term reading test scores by approximately 16 percentile points. The study, published this week by the Annenberg Institute for School Reform, is the first randomized-control test (RCT) of the long-term effects of any knowledge-rich curriculum on reading scores in elementary school.
To put the 16-point gain into perspective: U.S. students placed 15th among 50 countries taking the 2016 PIRLS 4th grade Reading/English test. But, if national student gains were similar to the gains realized in this intervention, the U.S. would place among the top five countries.
Although short-term RCTs on the effect of a knowledge-rich curriculum have been published, this is the first long-term study and the first to show sizable effects on a state standardized test.
Eight of the nine schools in the study, all of which were in the greater Denver, CO area, had mostly the children of middle- and high-income parents. At the remaining school, the curriculum showed even larger effects on English Language Arts, and significant benefits in math and science. These gains were large enough to eliminate the achievement gap associated with income.
The six-year study used a lottery methodology: 2,310 students applied to attend one of nine charter schools that use the Core Knowledge Curriculum, beginning in kindergarten. The 688 students selected in the lottery were compared to unselected students who attended school elsewhere. The outcome measures were student scores on the Colorado state-wide PARCC (Partnership for Assessment of Readiness for College and Careers) tests for English Language Arts and Math collected yearly from third through sixth grades. Scores from a state science test (designed by CTB/McGraw-Hill and administered only in grade 5) were also assessed.
An unexpected result in this study was differential attrition by gender. The parents in this study reacted differently when a boy lost the lottery than when a girl did. Likely because parents view boys as less mature at kindergarten age, they were more likely to keep boys at home for one more year and try the lottery again, or to pay for a private school. For girls who lost the lottery, parents were more likely to send them to the local public school. This differential attrition biased results and required new analytic procedures to assure unbiased results; these unbiased results are reported in the study.
The Core Knowledge Curriculum is based on the ideas and research of E.D. Hirsch, founder of the Core Knowledge Foundation. The curriculum has been in use since the 1990s and is currently used in approximately 2,000 schools in the U.S. It centers on a sequence of topics that integrates knowledge from the seven subject areas across K-8 grades to systematically build their knowledge and comprehension of the world.