Why Knowledge-Rich Curriculum Never Wins

It’s not a lack of evidence. Ideological, professional, structural, and political obstacles remain—and many of them are fixed features of American education.

Last week, I spoke to a group of young education policy professionals about literacy, the “science of reading,” and knowledge-rich education. It’s a talk I’ve given in one form or another for years. I walk audiences through a series of demonstrations showing that reading comprehension is not simply a matter of decoding words on a page. Background knowledge matters. Vocabulary matters. Context matters. What readers already know largely determines what they can understand.

This isn’t an original argument; E.D. Hirsch, Jr., has been making it for over 40 years. I became a convert teaching 5th grade in the South Bronx years ago in a classroom full of kids who could decode but struggled with comprehension. I’ve said countless times that Hirsch alone among theorists uncannily described and diagnosed my students’ struggles as if he’d been standing in my classroom.

Twenty years later, acceptance of evidence supporting knowledge as a driver of language comprehension has never been stronger. The science of reading movement, cognitive science, and research on reading comprehension have only strengthened the case for knowledge-rich education. Even artificial intelligence, unexpectedly, bolsters the argument: The better AI gets, the more obvious it becomes that people who possess broad knowledge, vocabulary, context, and judgment are able to use these tools more effectively than those who do not.

Recently, Chad Aldeman made precisely this point. For years, educators argued that students no longer needed to know things because information was readily available. AI exposes the weakness of that argument. Looking something up is not the same thing as understanding it. Nor is asking a chatbot a good question possible without already knowing quite a lot.

Curriculum advocates tend to speak as though the argument is over and the evidence is finally on their side. It is. But evidence was never the main obstacle. The obstacles are ideological, professional, structural, and political. Many are deeply embedded in the culture of American education. Some are embedded in American society itself. And to be brutally frank, many obstacles to knowledge-rich education are not viewed as obstacles at all: They are intellectual and even moral commitments that many school leaders and education advocates believe more important to defend and protect than knowledge-rich curriculum.

Let me enumerate them. And brace yourself, it’s a long and daunting list.

Ideological Obstacles

1. The Skills Myth
No single idea has done more to marginalize knowledge in American education than the belief that schools should focus on teaching critical thinking, problem-solving, creativity, and other “skills.” Critical thinking is not a generic skill that can be taught independently of content. The ability to think critically about the American Revolution does not automatically transfer to genetics, economics, or constitutional law. Thinking depends on knowing. If critical thinking is largely domain-specific, then knowledge is not merely one educational goal among many. It becomes the foundation upon which nearly every other goal or intellectual accomplishment rests. Yet much of American education continues to treat knowledge as negotiable and skills as the goal. Hirsch, Dan Willingham, and others have spent decades arguing that the relationship works in the opposite direction.

2. Child-Centered Learning
Knowledge-rich education assumes that adults have an obligation to introduce children to a world larger than themselves. Much of modern education assumes that learning should be driven by students’ interests, experiences, and preferences. These are competing and largely incompatible visions of education. The child-centered impulse animates everything from “culturally relevant” pedagogy to the popular notion that books should serve primarily as “mirrors” in which students see their own identities, cultures, and experiences reflected. There is obvious value in helping students feel seen and connected to what they learn. But much of what educated adults know was not acquired because it felt personally relevant at the time. It was acquired because schools deliberately introduced students to people, places, ideas, and events beyond their own experience. The promise of education is to encounter the larger world. A curriculum built primarily around mirrors will inevitably devalue windows.

3. Project-Based Learning
Knowledge-rich education assumes that domain-specific knowledge is the primary purpose of schooling and that it must be built deliberately, systematically, and cumulatively over time. History is best taught chronologically, science concepts build upon one another, and so on. In all subjects, vocabulary and background knowledge accumulate year after year, creating the “schemas” that make comprehension, reasoning, and critical thinking possible. Project-based learning treats knowledge not as body of content to be mastered but a tool acquired “just in time” to solve a problem or answer a question. Students learn what they need when they need it. It’s fundamentally a different theory of how knowledge is acquired and organized.

4. Anti-Canon Sentiment
A coherent curriculum requires somebody to decide what is worth knowing. For many educators, that immediately raises concerns about representation, exclusion, and power. Arguments about who should be included in the curriculum frequently overwhelm arguments about the importance of having one at all.

5. Individualism
Knowledge-rich education rests on an unfashionable proposition: There are some things everyone should know. Contemporary educational thought and practice, with its emphasis on personalization and student voice, moves in the opposite direction. But the tension runs even deeper than classroom practice: Individualism is woven into the fabric of American culture. From the founding period onward, Americans have celebrated independence, self-direction, and resistance to authority. Alexis de Tocqueville observed it nearly two centuries ago. Irving Kristol described Americans as possessing an “amiable philistinism“ toward books and intellectual life—a democratic suspicion that no small group of cultural authorities should decide what everyone ought to know. The notion that that schools have an obligation to transmit a common intellectual inheritance can sound uncomfortably elitist. For Hirsch and his followers, it sounds like the very purpose of schooling.

Professional Obstacles

6. Teacher Autonomy
Teacher autonomy is a cherished norm in American education. Many teachers view lesson planning—selecting texts, adapting materials, and crafting instructional experiences—as essential expressions of their professionalism. This creates an obvious challenge for knowledge-rich education, because a coherent, cumulative curriculum depends on consistency across classrooms and grade levels; what students learn in one year should deliberately prepare them for what comes next. But that level of coordination inevitably places limits on individual discretion. Teachers are asked to see themselves not primarily as independent instructional designers, but as participants in a larger enterprise of knowledge-building. Curriculum advocates see this as a support for teachers. But teachers may perceive it as a loss of status.

7. Curriculum as Resource Rather Than Roadmap
American educators have long treated curriculum as merely a resource rather than well-designed, coherent and cumulative course of study. Teachers are expected and encouraged to adapt, supplement, curate, and modify the curriculum, which often amounts to writing lessons from scratch. Published curricula are often held in low regard and viewed as raw materials in need of significant revisions. Walk into many schools and you will find teachers drawing lessons from multiple programs, websites, trade books, and self-created materials in pursuit of student engagement or instructional novelty. It makes sense that that curriculum should be malleable if one views it primarily as a tool for delivering skills and doesn’t care about delivering a sequenced body of knowledge. But for coherent knowledge-building, this practice is fatal.

Similarly, when districts adopt strong curricula, they often fail to implement them intentionally, rigorously, or with stamina. Teachers modify them. Administrators layer additional initiatives onto them. Supplemental materials crowd them out. Professional development reframes them. Over time, coherent curricula are often diluted into something much less coherent.

8. Weak Teacher Content Preparation
Many teachers receive extensive training in pedagogical theory but relatively little in history, science, geography, literature, or civics. Knowledge-rich education assumes content expertise that teacher preparation programs have not always prioritized or valued.

9. The Myth of the Heroic Teacher
Many educators continue to believe that exceptional teaching can compensate for weak curriculum. Advocates of knowledge-rich education tend to view the relationship differently. The point of a coherent curriculum is not to replace excellent teachers. It is to make success more achievable for ordinary teachers working under ordinary conditions.

Structural Obstacles

10. Local Control
Many Americans rightly value local control. But local control inevitably produces variation. A nation that allows thousands of districts to make independent curricular decisions is unlikely to arrive upon a coherent sequence of knowledge shared by all students. Students pay the cost of this school-to-school variation in curriculum. After all, U.S. students are among the most mobile in the world: A University of Michigan study found that by the time children were in the third grade, only 55 percent were in the same school where they began kindergarten. Another study showed that fewer than one in five (18 percent) of students remain in the same residence between kindergarten and twelfth grade. Knowledge-rich curricula depend on sequence. Sequence depends on continuity. Students who move frequently between schools and districts without a common curriculum inevitably encounter gaps, repetition, and inconsistencies.

11. Leadership Churn
Knowledge-building requires patience. School systems often lack it. Even where superintendents, principals, and school boards are persuaded by the evidence for a knowledge-rich approach, frequent leadership changes mean that schools adopt instructional changes long before a curriculum has had time to take root and bear fruit.

12. Innovation and Initiative Overload
Knowledge-building is cumulative, repetitive, and often unglamorous. By contrast, education’s culture and career paths tend to reward novelty and “innovation.” School leaders are constantly searching for the next breakthrough while neglecting the slow work of building knowledge over time. For these reasons, schools rarely stop doing new things. New initiatives accumulate without old ones disappearing: SEL. Personalized learning. Project-based learning. Competency-based education. AI integration. Restorative practices. Curriculum becomes one priority among many rather than the central mission of schooling.

13. Accountability
Knowledge-rich education is cumulative, particularly in literacy. As Hirsch observes, language proficiency is “a slow-growing plant.” By contrast, accountability systems are annual and impatient. Schools and teachers are judged on short-term performance indicators, making it difficult to sustain long-term investments in knowledge-building. Moreover, annual reading tests often explicitly encourage skills-based approaches to reading comprehension—find the main idea, make interferences, compare and contrast—that either thwart or rob time from coherent knowledge-building.

14. Educational Pluralism
I support school choice. I want to see broad, diverse, and effective school models from classical and experiential schools to microschools and homeschooling. I unequivocally support the right of families to choose among different educational models and philosophies—including some I might not personally hold in high regard. But honesty requires acknowledging the tradeoff: The more successful educational pluralism becomes, the harder it becomes to maintain a common body of knowledge. Choice sits uneasily alongside coherence.

15. The U.S. Constitution
Obviously, the Constitution does not explicitly prohibit knowledge-rich curriculum, but the word “education” does not appear in the document. And under the 10th Amendment, any powers not explicitly granted to the federal government by the Constitution are reserved for the states or the people. The result is the most decentralized education system in the world. Countries that successfully implement coherent curricula tend to do so through national systems. The United States has no comparable mechanism and never will. Whatever virtues this arrangement may have—and there are many—50 states and 14,000 school districts make coherence more difficult. As battles over Common Core reminded us, Americans prefer state and local control over uniformity. We should simply be honest that we have made that choice.

Political Obstacles

16. Curriculum Wars
History, literature, civics, race, gender, religion—every subject can become a political battlefield. The result is that many leaders avoid ambitious curricular decisions altogether. Conflict becomes a deterrent to coherence.

17. Equity Concerns
Ironically, one of the strongest arguments for knowledge-rich curriculum is an equity argument. Hirsch’s central insight was that schools often assume knowledge that many children have never had the opportunity to acquire. Middle-class and affluent students are more likely to absorb broad vocabulary, historical references, scientific concepts, geographic knowledge, and cultural literacy through conversation, travel, books, media, and family experiences. Less advantaged students are often expected to infer this knowledge as they go. When schools focus primarily on skills while treating knowledge as incidental, they inadvertently widen these disparities. A coherent, cumulative curriculum seeks to ensure that all students—not just the fortunate—have access to the shared knowledge that underpins reading comprehension, academic success, and civic participation. Yet critics often view common content as exclusionary or inequitable, creating one of the great paradoxes of modern education: A reform designed in part to promote equity is frequently opposed in the name of equity. Knowledge-rich education does not eliminate inequality, but it refuses to assume that schools are powerless to address it.

18. Distrust of Authority
Knowledge-rich education requires somebody to decide what children should know. While Americans have a congenital aversion to technocracy and rule by experts, our present era is notable for its particularly steep declines in trust in institutions, experts, universities, and public authority.

Technology

19. Artificial Intelligence
This may be the newest obstacle and the most paradoxical. AI demonstrates the importance of knowledge because knowledgeable people use it better. Yet it also creates the illusion that knowledge acquisition can be bypassed. Students can summarize books they have not read, explain concepts they do not understand, and write polished essays on subjects they know little about. The technology simultaneously validates Hirsch’s argument and tempts us to ignore it.

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Notice something about this list: None of these obstacles are disputes about cognitive science. Most analysts and advocates now accept that knowledge matters. There is nearly universal acceptance that reading comprehension depends heavily on what readers already know. Said differently, the obstacles to knowledge-rich education are not scientific; they are ideological, professional, structural, political, cultural, and increasingly technological. That should be sobering for curriculum advocates. It is a profound misunderstanding of the current moment to assume that knowledge-rich education is merely a matter of implementation.

The reality is far more daunting. Knowledge-rich education does not confront a single opposing ideology. It confronts a sprawling coalition of competing values: autonomy, personalization, local control, choice, relevance, pluralism, innovation, flexibility, and distrust of authority. Many of these values are worthy. Some of them I support myself. Yet every one of them makes it harder to organize a single school—let alone the nation’s schools—around the deliberate accumulation of shared knowledge.

Curriculum advocates often speak as though the evidence is finally on their side. It is. But evidence was never the obstacle. Proponents of knowledge have won the argument. But they haven’t won schools.

—With Annika Hernandez