Skip to content
Search AI Powered

Latest Stories

Outdated 'Facts' People Were Actually Taught In School

Reddit user BiAdventureTime asked: 'What’s an outdated “fact” that you were taught in school that has since been disproven?'

Make us preferred on Google

If you went to elementary school around the same time I did, you learned that there are nine planets in the solar system. Then, in 2006, it was decided Pluto did not fit the bill when it came to requirements for being a planet.

Suddenly, there were no longer nine planets in the solar system. There were only eight.

The solar system having nine planets is an outdated fact, since it used to be fact, but is no longer true. This happens quite often.

We learn something, accept it as fact, and then its disproven and becomes outdated.

A lot of what we learn in school are considered outdated facts. We learn a lot of things that aren't true, or were true at one point, but aren't anymore. Redditors know this all to well and are eager to share their stories.


It all started when Redditor BiAdventureTime asked:

"What’s an outdated “fact” that you were taught in school that has since been disproven?"

The Perfect Diet

"The food pyramid"

– Froticlias

"I have a clear memory of a grade school health teacher telling us that we were only supposed to have 1 gram of fat per day. She held up a packet of 2 Reese's Peanut Butter Cups which has like 5 grams of fat in it, and we asked if we'd have to have 0 grams of fat for five days in order to have that, or just eat a sliver of one peanut butter cup."

"Super bogus stuff. I know it's not healthy to eat peanut butter cups all day, but your brain needs fats to live."

– weenertron

Bird's Eye View

"You can see The Great Wall of China from space (ISS)"

– azazeLiSback

"This was always a weird one. The Great Wall of China is long but it's not that wide. If you could see it from space surely you'd be able to see roads and smallish buildings so it wouldn't be that impressive."

– AP246

"I didnt believe you. Googled it. You were right. This should be the top comment. That lie has been so ingrained into my brain. Wow."

– Boomshockalocka007

Crack, Crack

"Cracking your knuckles causes arthritis"

– MosesOnAcid

"This is a reminder that your knuckles are reloaded, feel free to crack them now."

– Crisis06

"I've always liked the story of Donald Unger, a doctor who cracked each knuckle on his left hand (but not his right) for 60 years to see if it contributed to arthritis (it didn't)."

"He won an Ig Nobel prize for it:"

– JinimyCritic

Before Smartphones

"You won't always have a calculator in your pocket"

– bread_makes_u_fatt

"That's actually true. Sometimes it's in my hands"

– dfreshcia

Bitter, Salty, Sour, Sweet, Savory

"Tastebud zones on the tongue."

– GrilledStuffedDragon

"I argued with my science teacher in 4th grade about this. Even to a 9/10 year old, this made no sense. She went to cafeteria and got some salt packets and sugar packets. We did a blind taste testing experiment. In the end, she had us draw an X through the picture in our science books. I have SOOOO much respect for teachers that can admit they are wrong. All people really, but especially teachers"

– whovian5690

Revolution!

"I was taught that Mercury was the hottest planet. A student corrected them on a national level and they changed how it was taught."

– KaJashey

Just Say No

"They told us that smoking one “marijuana cigarette” was equivalent to smoking 20 cigarettes and was 10X more carcinogenic."

– Jeramy_Jones

"We were also told that if we tried weed, we'd also want to try other drugs."

– Sadimal

"This is a hot frying pan. This is an egg. This is your brain on drugs.. sizzle, sizzle, sizzle."

"Holy crap, I was immediately convinced. /s"

– MsMisty888

Centimeters, Not Inches

"The US will be using the metric system in 10 years."

– Merrybee16

"I can remember being in 2nd grade, and one day the teacher stopped class for us to listen to the principal read this very serious speech over the PA system announcing that the metric system was coming. For some reason we all thought it was changing that day, and that there was a test after. Seriously, some kids cried. This was in the 70’s…lol."

– Speakinmymind96

"The reality is that the US will be using the metric system in 12 and 5/8 years."

– ClownfishSoup

Blue Bloods

"Blood is blue in your veins, but turns red when it hits oxygen. Idk if it was really a fact then or been disproven but I've learned it's not true."

"8th grade health class teacher taught us that."

– ninreznorgirl2

"Such a weird myth. It seemed fishy to me even when the teacher was telling us this is in second grade."

"Seems like a logical leap someone made because they looked at their arm and saw blue veins"

– mothwhimsy

"Our veins are blue simply because of the light spectrum."

"I can't remember the exact reasons, but it's something to do with blue being one of the colours that isn't filtered by our skin as well."

– Drakeskulled_Reaper

"This is one my mom told me my whole childhod and I didn't question. I believed it until as late as the 9th grade. There, in basic biology class, my teacher stated like it was sooo obvious that everyone knew blue blood was just a myth, and she was like "Nobody here thought that right?" I didn't raise my hand. I just stayed silent."

– RamenTheory

Cause and Effect

"Growing up, I was literally led to believe (and definitely not the only Black person), that Eli Whitney, inventor of the cotton gin, was Black."

– yhpargotohpts

"Not to mention, his invention of the cotton gin reinvigorated the cotton industry, which in turn reinvigorated slavery, which was starting to fade a bit because the labor of cotton wasn't worth it. With the cotton gin, they could process a lot more cotton, and slavery became worth it financially again."

– VillageSmithyCellar

"I was taught this as well. The Cotton Gin helped rid the US of slaves because they no longer needed to pick out those pesky seeds by hand."

"Nope. Made slavery more profitable. Larger profit margins = more slaves."

– Hoopajoops

Hand Me The Screwdriver

"The difference between man and animals is that animals don’t use tools."

"Myth busted."

– tikivic

"Chimpanzees have entered the chat. And capuchin monkeys. And crows. And octopus. And sea otters. And..."

– Agreeable-Damage9119

20/20

"Carrots help vision. "

– waconaty4eva

"Carrots do technically have some things on that your eyes need. But they do not improve your vision. I believe it was a rumour started by Britain so the Germans didn't realise we had radar."

– Donut_Klutzy

Rarely True

"I before e except after c"

– Horrorbmoviepunk

"Unless your feisty beige foreign neighbor invites you on a heist."

"Edit, missed one......invites you on a sleigh heist."

– NetDork

"…except sounding like “a” as in “neighbor” or “weigh,” except for eight exceptions including weird."

– spiderwebs86

Steer Correctly

"I was taught that you put your hands on the steering wheel at 10 and 2. My teen daughter learned this summer to put her hands at 9 and 3 in Drivers Ed. Apparently it’s safer if/when air bags are deployed."

– TraaashTVaddict

"A lot of drivers education programs are starting to teach 8 and 4 now."

– AgentOOX

"Can't wait until they finally get to my preferred "one on six, the other f**king with my radio.""

– Dogstile

The world is always evolving and changing, so education must too.

Are there any "facts" you'd like to debunk? Let us know in the comments below!

More from Trending/best-of-reddit

Ryan Reynolds as Deadpool at Comic-Con
@vancityreynolds/Instagram

Ryan Reynolds Secretly Crashed Comic-Con As 'Jeanpool'—And Fans Had No Idea It Was Him

Ryan Reynolds may be a well-known actor, but he's undeniably best known for his portrayal of the talkative and witty antihero Deadpool. And, over the years, Deadpool has had quite the objective over the years of joining the Avengers.

Reynolds' latest act on behalf of making Deadpool's dreams come true came in the form of sneaking into San Diego's Comic-Con dressed as a denim-clad version of Deadpool, or shall we say, "Jeanpool."

Keep ReadingShow less
Screenshots of Lindsey Graham
AJA Productions USA LLC

New Documentary Footage Of Lindsey Graham Gleefully Laughing After Convincing Trump To Attack Iran Is Chilling AF

New footage from an unreleased documentary shows the late South Carolina Republican Senator Lindsey Graham laughing after his years-long campaign to have President Donald Trump start a war with Iran paid off.

Graham died on the evening of July 11 after returning from an official visit to Ukraine. According to a preliminary finding from the medical examiner, shared by his office, Graham died after suffering an aortic dissection—a tear in the inner wall of the aorta—linked to hardening of the arteries.

Keep ReadingShow less
David Jonsson attends the Marvel Studios Panel at the 2026 San Diego Comic-Con.
Alberto E. Rodriguez/Getty Images for Disney

Actor David Jonsson Shares Humbled Reaction After He's Announced As New Black Panther At Comic-Con

The Marvel Cinematic Universe has found its next Black Panther.

During Marvel Studios' Hall H presentation at San Diego Comic-Con on Saturday, director Ryan Coogler announced that The Long Walk star David Jonsson will take on the mantle in Black Panther 3. Hours later, Jonsson shared a heartfelt reaction on Instagram, calling the moment "surreal" and thanking fans for their support.

Keep ReadingShow less
Carly Simon
Jim Spellman/WireImage

Fans Rally Around Carly Simon After She Reveals Parkinson's And Skin Cancer Diagnosis

Music legend Carly Simon has received an outpouring of support from fans after revealing a distressing diagnosis.

Simon issued a statement July 27 explaining that she's been diagnosed with Parkinson's disease, just months after having undergone treatments for skin cancer.

Keep ReadingShow less
Elliot Page
The Daily Show/Comedy Central

Elliot Page Just Revealed Why He Was More Prepared For Filming 'The Odyssey' Than Some Of His Castmates—And It Makes Sense

The cast of Christopher Nolan's adaptation of the ancient Greek epic poem Odyssey has been doing publicity for the film, which premiered on July 17 in the U.S. and UK.

The Odyssey has been dominating the box office after dominating the minds of MAGA minions (and Elon Musk) and other White supremacists for over a year, thanks to Nolan's choice to cast diverse actors instead of an all White, cisgender cast.

Keep ReadingShow less