RE (2024) — Appendix Iii
Appendix Iii
Appendix III details the Grissmer study, the first experimental study to rigorously document the outsized impact of a knowledge-based curriculum on student literacy. By analyzing randomized kindergarten lotteries in Colorado, the study found that students in Core Knowledge schools achieved a 16-percentile-point boost in reading scores compared to their peers, suggesting that building knowledge is a critical, often overlooked lever for accelerating literacy.
Argument Chains (6)
How the chapter's premises build toward conclusions. Each chain shows a line of reasoning from top to bottom. Click any node for full evidence and counter-arguments.
Causal Proof of Knowledge-Based Schooling strong
A young child's knowledge of the social and physical world is a strong predictor of their academic success in elementary school.1 ev
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Students with high background knowledge of a topic outperform students with high general reading skills but low topic knowledge in comprehension tasks.2 ev
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Excluding the youngest lottery applicants and lotteries with high differential attrition prevents parental 'redshirting' and attrition bias from skewing study results.1 ca
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Students who attend Core Knowledge charter schools achieve significantly higher scores in reading, math, and science in grades 3-6 than comparable students not offered admission.1 ca
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The educational gain from attending a Core Knowledge charter is equivalent to 16 percentile points in reading for a typical student.
The Empirical Validation Chain strong
The reading achievement gain found in the study is specifically compared to the performance levels of U.S. 13-year-olds on the 2016 Progress in International Reading Literacy Study (PIRLS).
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The achievement gains associated with Core Knowledge curriculum appear to stabilize by the 4th grade.
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Core Knowledge charter schools provide greater academic benefits for female students than for male students across all subjects.1 ca
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Building knowledge is a critical foundation for student literacy and produces potentially lifelong academic benefits.1 ca
The Literacy Foundation Chain strong
Component skills of literacy are critical to student development and learning.
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A full description of cognitive development involves a tripartite relationship: skill begets skill, knowledge begets knowledge, and skill combined with knowledge begets them both.
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A stronger approach to reading instruction can only grow from a foundation of broad knowledge.
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Skillful reading and broad knowledge should be the shared starting point for education.
Cognitive Multiplier Effect moderate
Skill building and knowledge accumulation are separate but complementary cognitive processes.
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The combination of skill and knowledge produces a multiplicative effect on learning.
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Current elementary school practices miss an opportunity to accelerate literacy by failing to build knowledge alongside component skills.
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The potential value of building student knowledge is frequently ignored in state and district efforts to improve reading instruction.
The Policy Implementation Chain moderate
Building knowledge is a critical foundation for student literacy and produces potentially lifelong academic benefits.1 ca
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A stronger approach to reading instruction can only grow from a foundation of broad knowledge.
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Elevating knowledge to a central priority in education policy requires a conceptual shift because 'building knowledge' is not intuitively linked to achievement in the public mind.
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Standardized national measures for elementary students should include well-designed assessments of student knowledge.1 ca
International Competitive Parity moderate
The educational gain from attending a Core Knowledge charter is equivalent to 16 percentile points in reading for a typical student.
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The achievement gain from knowledge-based schooling is equivalent to the gap between mediocre U.S. reading performance and that of top nations like Singapore and Finland.1 ev
Counter-Arguments (6)
alternative explanation (2)
The long-term impacts observed might be due to the 'cumulative' nature of charter school attendance (7 years) rather than the 'knowledge-based' curriculum itself; any consistent curriculum might produce similar stability.
The 'outsized impacts' found in the study may be due to the 'charter school effect'—where parents who enter lotteries are more engaged—rather than the Core Knowledge curriculum itself.
methodological concern (2)
Despite adjustments, the fact that winners were 5% more likely to stay in the testing pool suggests that the 'lottery winner' group might be more stable or motivated than the 'loser' group.
National knowledge assessments are politically impossible in a decentralized system and would lead to irreconcilable conflicts over which specific cultural facts are included.
scope limitation (2)
The study sample consists mostly of 'high- or middle-income families' who have the resources to enter multiple lotteries, meaning the results may not generalize to the disadvantaged populations most affected by the literacy crisis.
If the study shows girls benefit more than boys, a skills-based approach might still be necessary to address the specific learning gaps that prevent boys from achieving the same gains as girls in a knowledge-rich environment.
Logical Gaps (5)
Unstated assumptions required for the arguments to work.
The results from Colorado charter school lotteries can be generalized to traditional public schools with less motivated parent populations.
critical
Attribution of the gains specifically to the 'Core Knowledge' curriculum content rather than other charter school variables like teacher quality, longer school days, or peer effects.
significant
Establishing that individual test score gains in specific charter schools translate to broader 'societal communication' and 'equal opportunity' for the nation.
significant
National standardized testing is the most effective mechanism for ensuring that schools prioritize building knowledge.
significant
The cognitive mechanisms by which knowledge builds literacy are the same for both genders, even if the magnitude of the benefit currently differs.
minor