April 17 2023 – Sonia Q. Cabell
A new working paper from The Annenberg Institute at Brown University was recently released reporting on a study by David Grissmer and colleagues out of the University of Virginia. The study reported impressive long-term effects of a school-wide approach to building knowledge across subject areas. Specifically, kindergarten children who attended charter schools committed to implementing the Core Knowledge Sequence had stronger reading scores in grades 3-6 as measured by standardized tests. To my knowledge, this is the first study of its kind to longitudinally examine the effects of a school-wide knowledge-building approach on later reading achievement.
The Importance of Knowledge-Building for Reading
Reading theory has long established that background knowledge is necessary for reading comprehension. We use our background knowledge to make inferences and “read between the lines” in a text. As we read, we also create an overall mental model about the ideas in a text, heavily relying on our background knowledge of a given topic.
The tricky part is that knowledge takes time to build and efforts to enrich children’s knowledge about the social and natural world should begin very early. Unfortunately, there is not a lot of time spent building children’s knowledge in U.S. public elementary schools. For example, Tyner & Kabourek (2020) reported that elementary school students in grades 1-5 spend a small fraction of time in science or social studies instruction, compared to time spent in English Language Arts.
We have encouraging evidence from a recent meta-analysis that integrating knowledge-building with literacy positively impacts comprehension (Hwang, Cabell, & Joyner, 2022). But there are very few longitudinal studies to date that examine whether building knowledge over time improves reading comprehension. [One notable exception is a recent study from James Kim and colleagues (2023).] Grissmer’s study is unique in that it studied knowledge-building across subjects for a period of several years.
Details of the Study
The study was a randomized controlled trial that compared children who had received admission to a charter school through a lottery system with those who applied but were denied admission. The children denied admission attended other schools in the area. The sample consisted of approximately 2,300 children who applied to at least one of fourteen kindergarten lotteries across 9 charter schools in Colorado primarily serving middle- and higher-income families. (The lotteries were for kindergarten entry at the start of the 2009-2010 or 2010-2011 school years).
The charter schools were committed to teaching the topics in the Core Knowledge Sequence. One of the distinguishing features of the Core Knowledge approach is that knowledge is sequenced coherently within and across years so that it builds over time. The Core Knowledge Sequence should not be confused with the popular Core Knowledge Language Arts program. The Sequence is a set of content standards in K-8 across subject areas and forms the basis for the curricular products developed by the Core Knowledge Foundation over time (e.g., CKLA). The sequence is described by its developers as “the blueprint for knowledge-based schooling” and subject areas included in the Sequence are: Language Arts, History and Geography, Visual Arts, Music, Mathematics, and Science. A grade-specific handbook was available to teachers that gave guidance on how to teach each subject but was not a packaged curriculum.
In a nutshell, the study reported that children who attended a Core Knowledge Charter School starting in kindergarten showed stronger reading achievement in grades 3 – 6 than those who attended a different school. While the effect sizes might be considered small to moderate, it is nonetheless impressive to see an impact on a measure of general reading comprehension, especially given that randomized controlled trials often result in no discernable impact on standardized measures.
The authors of the study acknowledge that the study has not yet gone through a rigorous peer-review process. That process will no doubt wrestle with the question of whether the effects generalize to regular public (non-charter) schools, especially urban public schools, and issues related to bias from differential attrition and the analytic strategy.
I would like to have seen more data and discussion on implementation of the Sequence in the study schools. We need to know the degree to which administrators and teachers in these charter schools were committed to a cumulative and coherent knowledge-building approach across grades, and how they were able to sustain the effort across multiple years. It would also be important to better understand the instruction to which control group children were exposed, in terms of English Language Arts as well as content-area instruction, but the difficulty in collecting these data is perhaps an inherent weakness of a lottery-based design.
This research stands out as an impressive longitudinal study on the effects of building knowledge on later reading. This is not just important for the Core Knowledge approach being studied but for all who are committed to a knowledge-building approach throughout elementary school. In short, a school-wide commitment to building knowledge matters. This kind of commitment can lead to coherent learning experiences for children both within and across years, perhaps leading to the kind of shift in national reading scores that we so desperately need.
Sonia Q. Cabell is Associate Professor of Reading Education in the School of Teacher Education and in the Florida Center for Reading Research at Florida State University. She is a member of the Knowledge Matters Campaign Scientific Advisory Committee.