Bridging the Gap Between Evidence and the Classroom

The Evidence Paradox

Educational research has reached a level of maturity rarely seen in the social sciences. Thousands of studies, systematic reviews, and meta-analyses have made it possible to identify with considerable precision which practices promote learning and which have little effect. Rarely has there been such broad consensus on issues as diverse as the importance of formative assessment, feedback, making learning goals explicit, and fostering students’ self-regulation.

Yet this body of knowledge coexists with a less encouraging reality. Differences between classrooms remain enormous, even within the same school. Strategies whose effectiveness has been widely documented do not always become part of everyday teaching practice, and even when they do, their results can vary considerably.

This apparent contradiction has shifted the focus of educational research. Attention is no longer directed solely at identifying practices that work, but at understanding why it is so difficult to incorporate them systematically into teaching. Applying evidence requires interpreting context, responding to changing needs, and making continuous decisions in situations where there is rarely a single correct answer.

This is precisely the question addressed in High-Quality Teaching: Building on What We Know, the report jointly produced by the OECD and SUMMA: how to turn the accumulated knowledge about effective teaching into a practical tool for those who, every day, must make decisions in front of a group of students.

Teaching Means Making Decisions Under Uncertainty

No teaching practice works in isolation. Research may demonstrate that certain strategies promote learning, but their impact depends on how they are combined, when they are used, and with which students. Teaching cannot be reduced to the application of a set of techniques, no matter how strong the evidence supporting them may be.

Every school day requires teachers to make decisions continuously. They decide whether to move on with the planned lesson or spend more time consolidating a concept that has not yet been understood; whether to rephrase an explanation after noticing signs of confusion; whether to modify an activity to maintain students’ attention; or whether to use an unexpected student intervention as an opportunity to explore an idea in greater depth. Many of these decisions are made in a matter of seconds and rarely follow a predetermined protocol.

The ability to interpret what is happening in the classroom is therefore an essential part of teaching. Scientific evidence provides valuable guidance on the practices that support learning, but it does not eliminate the need to consider the context in which those practices are implemented. Students’ age, prior knowledge, classroom climate, learning objectives, and the time available all influence the way teaching unfolds, just as much as the instructional strategy itself.

For this reason, the same practice can produce different outcomes. Feedback is one of the most extensively studied examples in educational research. Its effects depend on numerous factors: when it is provided, the information it contains, whether students have the opportunity to act on it, and how it is integrated into the learning sequence. Simply incorporating feedback into a lesson is not enough; how it is used and for what purpose also matter.

This understanding of teaching shifts attention away from the mere adoption of effective practices toward the development of professional judgment. Knowing the evidence is essential, but teaching also requires the ability to interpret, adapt, and combine that evidence in response to constantly changing circumstances. Experience, initial teacher education, collaboration with colleagues, and reflection on one’s own practice all contribute to building this professional capacity.

Reducing the distance between research and classroom practice therefore depends on more than generating additional knowledge about how students learn. It also requires strengthening the conditions that enable teachers to transform that knowledge into sound pedagogical decisions. Evidence guides practice; professional judgment is what makes it possible to apply it where it matters most: in the classroom.

The Practices That Define High-Quality Teaching

The report identifies twenty evidence-based teaching practices and organizes them into five broad dimensions, ranging from planning to assessment. These are neither new proposals nor fashionable methodologies. Many have long been part of the everyday work of effective teachers. What research contributes is a more precise explanation of why they work, the conditions under which they produce better results, and how they interact with one another.

The first dimension concerns creating an environment conducive to learning. Maintaining a respectful classroom climate, setting high expectations for all students, and building positive relationships are not secondary considerations. Evidence shows that these conditions influence students’ participation, motivation, and willingness to engage in intellectual challenges. Learning requires feeling safe enough to make mistakes, ask questions, and participate actively in class.

The second dimension brings together practices directly related to instruction. Clearly defining learning objectives, presenting content in a structured way, using examples to help students understand complex concepts, and connecting new ideas to prior knowledge all help students build more robust learning. Cognitive science has shown for decades that learning does not consist of simply acquiring new information, but of integrating it with what learners already know.

Assessment occupies a central place in the framework proposed by the OECD and SUMMA. It is not viewed as a mechanism for assigning grades at the end of a teaching unit, but as a tool that accompanies the entire learning process. Asking questions that reveal students’ understanding, identifying misconceptions before they become entrenched, or providing specific feedback benefits both students and teachers. Students receive information that helps them improve their work, while teachers gain insights that allow them to adjust instruction while there is still time to do so.

Another dimension emphasizes students’ active participation. Solving problems, debating, constructing arguments, explaining ideas to classmates, or applying knowledge in different situations all promote deeper understanding than simply receiving information. Research consistently shows that learning involves constructing, connecting, and using knowledge, not merely remembering it.

The framework concludes with a set of practices aimed at developing students’ autonomy. Planning one’s own work, monitoring progress, identifying difficulties, and reflecting on the strategies used are all skills closely linked to self-regulated learning. Students who learn to evaluate their own learning process are better prepared to continue learning both inside and outside school.

These twenty practices form an interconnected system of decisions that reinforce one another. Clear explanations lose much of their effectiveness if teachers do not subsequently check what students have understood. Feedback is of limited value if students are not given opportunities to revise their work. Promoting autonomy, in turn, requires clear objectives and ongoing monitoring. The quality of teaching does not depend on applying a single practice in isolation, but on the ability to combine them coherently according to the needs of each classroom.

What Makes an Educational Practice Work?

If evidence-based practices were sufficient on their own, simply disseminating them and training teachers would eventually ensure that they became part of classroom practice. Experience shows that this is not the case. The report draws on case studies from more than 150 schools across 40 countries to understand what enables—and what hinders—the sustained implementation of these practices.

Instructional Leadership

One of the factors that consistently emerges is instructional leadership. Schools that achieve sustained improvements in teaching are typically led by leadership teams that make learning a shared priority. They do more than manage resources or resolve administrative issues; they create opportunities for teachers to observe lessons, examine evidence of student progress, exchange experiences, and reflect collectively on their practice.

Time to Think About Teaching

Time is another decisive factor. Preparing a well-designed sequence of lessons, creating learning activities, analysing students’ work, or adjusting planning based on assessment all require a resource that is scarce in most education systems: time to think about teaching. When the entire working day is consumed by classroom instruction and administrative responsibilities, it becomes far more difficult to introduce changes, however well supported by evidence they may be.

Professional Collaboration

Professional collaboration also plays a prominent role. Much of teachers’ knowledge is tacit: it is built through practice and refined through interaction with colleagues. Schools that encourage peer observation, collaborative planning, or professional learning communities create more opportunities for evidence to move beyond individual reading and become a shared resource for solving concrete educational challenges.

Continuous Professional Development

Professional development also takes on a different meaning. The report questions models based on one-off courses disconnected from classroom reality. Professional learning opportunities have a greater impact when they are linked to teachers’ everyday challenges, include ongoing support, allow teachers to experiment with new practices, and provide time to reflect on the outcomes.

This perspective shifts part of the responsibility from individual teachers to the education system. The quality of teaching depends on teachers’ knowledge and commitment, but also on the conditions that enable them to exercise their profession rigorously. Evidence-based practices require schools capable of sustaining them and policies that view educational improvement as a continuous process rather than the periodic introduction of new methodologies.

This shift in perspective has important implications. Turning evidence into a tool for improvement is not simply a matter of producing more research or disseminating new recommendations. It requires building learning organizations that foster trust among professionals and provide the time, leadership, and collaborative spaces needed to transform knowledge into practice. This is where evidence ceases to be a collection of general principles and begins to shape the everyday experiences of teachers and students.

From Evidence to Practice

Educational research will continue to advance. New studies will emerge, existing hypotheses will be revised, and new evidence will appear on strategies that are only beginning to be explored today. This is part of the normal progress of science and will continue to enrich our understanding of how people learn. Yet the report encourages us to look elsewhere. The priority no longer seems to be expanding the catalogue of effective practices indefinitely, but increasing education systems’ capacity to implement them consistently.

This shift in perspective requires understanding educational improvement as a collective endeavour. High-quality teaching depends not only on the preparation of individual teachers, but also on schools’ professional culture, opportunities for peer learning, leadership that supports innovation, and policies that provide the stability needed to consolidate change. Evidence remains of little value when it is confined to academic papers, reports, or training programmes; it begins to transform education when it becomes part of the everyday decisions made in classrooms.

Research has reduced many of the uncertainties surrounding how students learn. The next step is to close another gap: the one separating that knowledge from everyday practice. This is not exclusively a pedagogical challenge. It also concerns the organization of schools, teacher education, and education policy. Evidence only acquires real value when it becomes part of the decisions made in classrooms every day.