Debunked Education Myths
Three debunked education myths
- Cobun retention percentages (1968): the claim that we remember 10% of what we read, 20% of what we hear, 50% of what we see and hear, 90% of what we say and do. No empirical basis. Will Thalheimer and others traced the figures through textbooks and found no original study.
- Left-brain / right-brain learners: the claim that some people are “logical, analytical” (left-brain) and others “creative, intuitive” (right-brain). Neuromyth. A 2013 fMRI study of 1,011 people (Nielsen et al., University of Utah) found no evidence for hemispheric dominance as a personality trait.
- Fixed learning styles (visual / auditory / kinesthetic): the claim that each student has a fixed style and teaching to it improves learning. Weak evidence. A 2008 review (Pashler, McDaniel, Rohrer, and Bjork) found almost no experimental support.
- Why they survive: they sound scientific, they are easy to put in a lesson plan, and they have been repeated for decades.
- The check: if “research shows X” cannot be traced to a primary study, treat it as unverified.
Many teacher-training programmes repeat a few claims that turn out, on inspection, to have no real evidence behind them. The claims sound scientific. They appear in textbooks, lecture slides, and training materials. Generations of teachers have been told them as fact, and some students are still being told them now.
A teacher who passes these on is repeating something they never checked. A teacher who verifies them first is doing information literacy on the same material they are training to teach. The evaluation routine from the previous article applies directly: each claim below fails on the question of evidence.
The Cobun retention percentages
A widely-cited figure claims that memory holds different fractions of information depending on the channel and the action.
The standard form of the claim is:
- 10 percent of what we read
- 20 percent of what we hear
- 30 percent of what we see
- 50 percent of what we see and hear
- 70 percent of what we say
- 90 percent of what we say and do
The figures are usually attributed to “Cobun (1968),” sometimes to Edgar Dale’s Cone of Experience (1946), and sometimes to no source at all.
When researchers have tried to find the original study behind these percentages, they have failed. Will Thalheimer, an instructional designer who traced the claim across decades of educational literature, found that the numbers appear in many textbooks but no source ever cites a primary experiment. The figures have been copied from one secondary source to another, attached to Dale’s name, to Cobun, or to no one, but never traced back to original data.
Dale’s Cone of Experience is a real diagram from 1946. It is a rough ordering of teaching activities from abstract (verbal symbols at the top) to concrete (direct experience at the bottom). Dale never attached percentages to any level of the cone. Later authors added the numbers and credited them back to him.
Modern memory research does not support fixed-percentage retention by channel. How much is remembered depends on how the material is processed, what the learner already knows, how it is tested, and how long after learning the test happens. There is no clean fraction to assign to “what we read” or “what we hear.”
The figures persist because they are useful for lesson-planning slides. They feel scientific and tell a tidy story. They are also wrong.
They sound scientific, they are easy to put on a slide, and they have been copied across textbooks for decades.
The numbers tell a tidy story: read 10%, see-and-hear 50%, say-and-do 90%. The story matches a real classroom intuition that active learning helps. But the specific percentages have no original study behind them. They became “research-backed” through repetition, not evidence.
The left-brain / right-brain framing
A common claim in education and self-help books is that the two hemispheres of the brain handle different kinds of thinking. The left is described as logical, analytical, mathematical, and language-focused. The right is described as creative, intuitive, artistic, and emotional. Individual people are then labelled “left-brained” or “right-brained” based on personality or career.
The popular framing is not supported by current neuroscience.
Real hemispheric specialisation exists. Language processing is strongly left-lateralised in most right-handed people. Spatial attention is often more right-lateralised. Faces are processed with a slight right-hemisphere bias. These differences are measurable and real.
But the leap from “some specialisation exists” to “people have a dominant hemisphere that defines their personality” is unsupported. A 2013 study by Jared Nielsen and colleagues at the University of Utah used functional MRI scans of 1,011 people to test for hemispheric dominance as a personality trait. They found no evidence that individuals are “left-brained” or “right-brained” in the sense the popular claim describes. Both hemispheres are active in almost all complex tasks, and the differences between people’s brains are not concentrated in one hemisphere versus the other.
The myth persists because the hemispheres are a vivid metaphor, the labels are easy to apply (“you are right-brained, that is why you struggle with maths”), and they give a reassuring explanation for difficulties that may have other causes.
A teacher who labels a student “right-brained” and adjusts teaching to that label is acting on folk psychology, not science. The adjustment may or may not help, but the reason behind it is wrong.
Fixed learning styles
A related claim is that each student has a fixed learning style (often visual, auditory, or kinesthetic) and that teaching to that style improves learning outcomes.
The first half of the claim, that students have preferences for how they receive information, is broadly true. The second half, that matching teaching to those preferences improves learning, has been tested experimentally, and the results are weak.
A 2008 review commissioned by Psychological Science in the Public Interest and authored by Harold Pashler, Mark McDaniel, Doug Rohrer, and Robert Bjork looked for experimental evidence that teaching to a student’s stated learning style produced better outcomes than teaching the same content in a different style. They found almost none. The studies that did exist were small and had methodological problems.
Their conclusion was that learning styles, in the strong form taught to many educators, is not well supported. The weak form, that varying instructional channels helps all students, is supported, but that is a much more modest claim than “match the channel to the student.”
This is a distinct claim from Howard Gardner’s Multiple Intelligences, which is also contested but rests on a different argument. Multiple Intelligences proposes that human intelligence has several capacities; learning styles proposes that each individual has a fixed delivery preference. The two are sometimes conflated and should not be.
The pattern these claims share
Three properties make an education myth durable even after it has been refuted.
It sounds scientific. Numbers, brain imagery, or named theorists give the claim authority. A claim that comes with a percentage feels more solid than one without, even if the percentage was invented.
It is easy to use in a lesson plan. A teacher can put “90 percent retention through doing” on a slide, or label a student “kinesthetic” and adjust homework. The claim hands the teacher a tool. A more accurate claim (“how much students remember depends on many interacting factors”) gives less to work with.
It has been repeated for decades. Textbooks cite other textbooks. Teacher trainers learned the claim from their own trainers. Removing a claim from the field is far slower than adding one.
A teacher who learns to spot this pattern can apply it to many other claims: the Mozart effect, the ten-thousand-hour rule, the myth that humans use only ten percent of their brains, and the various claims about generational differences in attention. Each has the same three properties.
It sounds scientific, it is easy to use in a lesson plan, and it has been repeated for decades.
- Sounds scientific
- Easy to use
- Repeated
A teacher who recognises this pattern can spot education myths before passing them on.
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