19 High School “Facts” Now Proven Wrong

Information evolves rapidly, so the facts we learned in high school may not hold up under the scrutiny of modern science and historical research.

This list explores commonly taught “facts” that have since been debunked or significantly revised, shedding light on the importance of continually updating educational content to reflect our current understanding of the world.

1. Pluto is the Ninth Planet

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Introduced as the ninth planet in 1930, Pluto’s status was reevaluated in 2006 by the International Astronomical Union (IAU). The decision to downgrade Pluto to a “dwarf planet” was based on criteria that required a planet to clear its orbit around the Sun, which Pluto does not do due to its overlap with the Kuiper Belt—a region of the Solar System beyond Neptune filled with other icy bodies.

2. Humans Have Five Senses

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The limitation of human senses to five is an oversimplification. Beyond sight, hearing, taste, smell, and touch, we can detect balance and acceleration, temperature, pain, and various internal stimuli (like hunger) that do not fall neatly into the original five categories.

Expanding our sensory understanding reflects a deeper comprehension of how we interact with our environment.

3. Taste Buds Are Sectioned Off by Taste

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This myth originated from misinterpreted 19th-century research and was perpetuated by poorly designed diagrams.

Modern research using advanced imaging techniques has shown that sweet, sour, salty, bitter, and umami taste receptors are distributed all over the tongue. However, some areas may have a slightly heightened sensitivity to certain tastes.

4. Christopher Columbus Discovered America

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Saying Columbus discovered America overlooks the millions of indigenous people already living on the continents. Moreover, Norse explorer Leif Erikson is known to have reached North America in the 11th century.

The narrative around Columbus has shifted towards recognizing the impacts of European colonization on indigenous populations.

5. Diamonds are Formed from Coal

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Most diamonds formed long before the first plants on Earth, which means they couldn’t have come from coal. The process requires extreme pressure and temperatures found 140-190 kilometers below the Earth’s surface, where carbon atoms bond in a unique arrangement under conditions that predate terrestrial plants by billions of years.

6. There are Only Three States of Matter

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This basic classification misses several other states, including plasma, a high-energy state of matter where electrons are stripped from atoms.

In addition, quantum physics has revealed states like Bose-Einstein condensates and fermionic condensates, which occur under extreme cooling or density and have unique properties that challenge our traditional understanding of physical states.

7. The Great Wall of China is Visible from Space

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This myth likely originated from overestimations of the Wall’s size and visibility. Astronauts have confirmed that, from orbit, human-made objects visible to the naked eye are those with significant contrast against the natural environment, and the Great Wall, often the same color and texture as the surrounding land, does not stand out.

8. Humans Evolved from Chimpanzees

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Humans and chimpanzees share a common ancestor that lived millions of years ago, from which both species evolved separately. This distinction is crucial for understanding evolutionary biology and the complex web of life that connects all living beings through shared ancestry rather than direct lineage.

9. Water Conducts Electricity

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The conductivity of water is actually due to the minerals and salts dissolved in it, which ionize and enable the flow of electrical current.

Pure water (H2O without impurities) has a very low conductivity, which is why distilled water is used as an insulator in certain applications.

10. The Color of Blood is Blue in Your Body

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Blood is always red due to the iron in hemoglobin, which binds with oxygen to transport it through the body. The misconception comes from the way light and skin interact and the color of veins, which can appear blue under the skin.

Deoxygenated blood is a darker shade of red but never turns blue.

11. You Can’t End a Sentence with a Preposition

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The rule against ending sentences with prepositions is based on Latin grammar, which is impossible due to the structure of the language. However, English is not bound by the same rules, and in practice, insisting on avoiding final prepositions often leads to awkward or overly formal sentences.

Modern grammarians accept sentence-ending prepositions, especially in cases where the preposition is part of a phrasal verb (e.g., “turn off”) or when rearranging the sentence would unnecessarily complicate the message.

12. The Brontosaurus Never Existed

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For many years, the Brontosaurus was considered a paleontological mistake, a duplicate of the Apatosaurus.

Recent findings, however, have supported the distinction between the two, with the Brontosaurus being reinstated as its own genus. This revision came after detailed comparisons of bone structures, demonstrating the dynamism of scientific understanding and classification.

13. Albert Einstein Failed Mathematics

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This myth misrepresents Einstein’s academic performance. While he did fail the entrance exam to the Swiss Federal Polytechnic School on his first attempt, it was not due to his mathematics or physics scores, which were actually quite high.

The failure was primarily in non-scientific subjects. Einstein’s contributions to math and physics, including the theory of relativity, underscore his profound abilities in these areas.

14. Slaves built the Pyramids

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Recent archaeological findings have uncovered evidence of well-organized communities of workers who lived near the pyramids they were building. These workers were skilled laborers, not slaves.

They were compensated with food, medical care, and a burial in the necropolis near the sacred pyramids, indicating a degree of honor and respect for their work.

15. Salem Witch Trials Executed Witches by Burning

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The misbelief that the Salem witch trials involved burning at the stake is likely conflated with European witch hunts. In Salem, the majority of those found guilty of witchcraft were hanged, with one notable exception being crushed under heavy stones.

This historical accuracy highlights the variations in execution methods in witch trials across different cultures and times.

16. Glass is a Slow-Moving Liquid

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Glass does not flow over time; it is an amorphous solid. The misconception arises from observing old windows, which are often thicker at the bottom.

This unevenness is due to the manufacturing processes of the past, where glass was less uniformly produced than it is today, not because it has flowed down over centuries.

17. Vitamin C Cures the Common Cold

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While vitamin C is crucial for immune function, research has consistently shown that taking vitamin C supplements does not prevent the common cold for the general population.

While it may slightly reduce the severity and duration of cold symptoms for some individuals, it is far from a cure.

18. We Only Use 10% of Our Brains

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This myth perpetuates a fundamental misunderstanding of brain function and has been debunked by neuroscientists. Brain imaging technologies have shown that nearly all parts of the brain have known functions and are active at various times, depending on the activity and the individual’s state of consciousness.

19. Bats Are Blind

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The phrase “blind as a bat” is misleading because all bat species have eyes and can see. While it’s true that many bats rely heavily on echolocation to navigate and find their prey in the dark, this doesn’t mean they are blind.

Some bats, especially fruit bats, have relatively good vision, which they use alongside echolocation.

Martha A. Lavallie
Martha A. Lavallie
Author & Editor | + posts

Martha is a journalist with close to a decade of experience in uncovering and reporting on the most compelling stories of our time. Passionate about staying ahead of the curve, she specializes in shedding light on trending topics and captivating global narratives. Her insightful articles have garnered acclaim, making her a trusted voice in today's dynamic media landscape.