When Jimmy Fallon says “It's Hashtags time!” we know we are about to chuckle, cringe, laugh and blow raspberries because the responses have an entertainment value unlike anything else.
“Tweet something funny or weird that you used to think and tag it with #IUsedToThink,” Fallon announced on Twitter before sharing his own story. “I used to think that if I turned on the light in the back seat while the car was moving, we would get pulled over by the police and my parents would go to jail for 50 years,” he recounted.
Now, the relay is on to the people on Twitter, who, inspired by the comedian’s challenge, are now sharing their most embarrassing, unstaged, and plain hilarious stories about things they were one hundred percent sure about (which they weren’t).
Scroll down through the responses below, upvote your favorite tweets and be sure to share your own contributions in the comment section below!

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aww, this is the sweetest thing I ever heard, giving you a bit of magic~ yet a slightly evil prank with mom to share with when you are older! "remember how you used to think they grew hahaha!"
It shouldn't really make a difference, they should all want the best for our country, but when half the country is stupid enough to vote for a sleazy reality tv host with zero political experience who brags about sexually assaulting women, it's time to adjust that expectation.
I used to make sure each toy was tucked into a little bed. Yes it did take me a long time to go to sleep at night.
Aww, poor dear. If only you’d had the courage to tell your adult relatives at the time; as (unless your fam love pranks) they surely would’ve put your mind to rest. 🥺
I think I would die if this was real. IMAGINE IF YOU WERE OUTSIDE IF A @&#$% WORM FELL ON YOUR HEAD
I learned this as a teen when my best friend died. My group of friends were so kind to each other, stopped gossiping, really put effort into letting each other know we cared. That lasted a few months and it slowly dissolved back to how it was before. I slowly pulled away from all my friends then picked a college none of them were going to. My friend dying did change me and it wasn’t a temporary thing. I picked different friends at college.
I used to tell my ex that the only "common cents" she has was the family change dish.... She never got it lol
Here’s something for our German speaking pandas: I lived in Germany for a few years as a child and teenager. One day, in primary school, the teacher prepared us for our first trip to the library. She explained that “die Bibliote Karin” will show us around. 7 year old me deducted from this that clearly “Bibliote” meant librarian and that her name was Karin.
Good thing you have a lot of breaks on American television or the house would have been in shambles. ✌️
This is a family joke. All the photos of when my parents were young are in black and white. So if something happened a long time ago, we say "back when the world was in black and white". There doesn't seem to be much evidence that things were in colour as they have very few possessions from back then. The 60s and 70s were definitely in colour as we have photos to prove it, plus I remember the (hideous) orange carpet that they had in the kitchen!
Mythbusters declared it pausible. It confirmed you could get electrocuted if you answer a landline during an electric storm.
As a kid, I used to think I was born before my parents were married because they were married in June and I was born in May (of the following year). It was so confusing...
LOL! Why was Madge having women soak their fingers in dish soap? What purpose did it serve?
Funnily enough my parents sold the house to the people they are renting from
I thought that any mother bird didn’t have legs so that she wouldn’t step on her eggs or chicks when she sat on the nest.
World famine could have been solved long ago if we had known that.
My grandmother refused to warm up the car because the electricity bill would get to high.
most people would make that mistake, especially outside usa. you're forgiven.
my Dad said the little guy that did this was named Yahooti. not sure of the spelling.
https://www.youtube.com/watch?v=VjPdFZsCY4Y ...forbidden pistachio ice cream.
Chief Broom in One Flew Over the Cuckoo's Nest called the medication that calmed him down "the fog machine" and he believed that there were real machines in the mental ward, such as the ones used by the military in WWII to hide ships.
"Robin! I think the Batmobile's Battery is flat! " - Batman. "What's a Tery?" - Robin.
I used to believe I was a freak, as I grew “unladylike” bodily hair when I began puberty & people who weren’t my loving relatives would suggest that I wasn’t a real female, because quote “that’s not normal for girls”. Years later, I was diagnosed with PCOS & I started to believe that I wasn’t the one who should feel shame. Now, I no longer care if people are of the opinion that I should be shaving everything just to please others. I’m comfortable in my own body & my legit fam support me all the way … so, if other people are uncomfortable; that’s their problem, not mine. 🤷♀️🙂
I used to think that banks kept your money in a drawer with your name on the front. So when you paid in money, they’d take it and put it in your drawer and lock it. This was way before internet/phone banking and I had no concept of credit/how money transactions worked. I was only about 5. We had drawers at school with our name on where we kept our books, that’s where the assumption must’ve come from!
I'm with you. When I was 5-6 I went with my mom to deposit a brand new $2 bill in my savings account. I didn't want to give it up because it was so beautiful. I said, "well, I can always come back and look at it sometime, right? RIGHT?"
Load More Replies...I used to think that if the world was ending (according to Dean’s Big Book of Answers it was in however many billions/trillions of years) and of course, I didn’t understand that timescale or basic geography. I thought it would be okay if we all went to Japan, I mean it’s far enough away, right?
I used to believe I was a freak, as I grew “unladylike” bodily hair when I began puberty & people who weren’t my loving relatives would suggest that I wasn’t a real female, because quote “that’s not normal for girls”. Years later, I was diagnosed with PCOS & I started to believe that I wasn’t the one who should feel shame. Now, I no longer care if people are of the opinion that I should be shaving everything just to please others. I’m comfortable in my own body & my legit fam support me all the way … so, if other people are uncomfortable; that’s their problem, not mine. 🤷♀️🙂
I used to think that banks kept your money in a drawer with your name on the front. So when you paid in money, they’d take it and put it in your drawer and lock it. This was way before internet/phone banking and I had no concept of credit/how money transactions worked. I was only about 5. We had drawers at school with our name on where we kept our books, that’s where the assumption must’ve come from!
I'm with you. When I was 5-6 I went with my mom to deposit a brand new $2 bill in my savings account. I didn't want to give it up because it was so beautiful. I said, "well, I can always come back and look at it sometime, right? RIGHT?"
Load More Replies...I used to think that if the world was ending (according to Dean’s Big Book of Answers it was in however many billions/trillions of years) and of course, I didn’t understand that timescale or basic geography. I thought it would be okay if we all went to Japan, I mean it’s far enough away, right?
