A woman in sub-Saharan Africa is part of a cutting-edge HIV clinical trial -- but she can't afford a bus ticket to her health clinic, let alone the life-saving antiretrovirals she'll need. Boghuma Kabisen Titanji asks an important question: How can researchers looking for a cure make sure they're not taking advantage of the people most affected ...

A bump on the head, a mysterious femme fatale and a strange encounter on a windswept peak all add up to a heck of a night for Manny Brot, Private Eye. Watch as he tries his hand at saving the dame and getting the cash! Shudder at the mind-bending geometric riddles! Thrill to the stunning solution of The Case of the Missing Fractals. [Directed by...

Taking that internship in a remote mountain lab might not have been the best idea. Pulling that lever with the skull symbol just to see what it did probably wasn't so smart either. But now is not the time for regrets because you need to get away from these mutant zombies...fast. Can you use math to get you and your friends over the bridge before...

Your favorite band is great at playing music...but not so great at being organized. They keep misplacing their instruments on tour, and it's driving their manager mad. Can you solve the brain-numbing riddle their manager assigns them and make sure the band stays on their label? Yossi Elran shows how. [Directed by Artrake Studio, narrated by Addi...

As your country's top spy, you must infiltrate the headquarters of the evil syndicate, find the secret control panel, and deactivate their death ray. But your reconnaissance team is spotty, and you have only limited information about the control panel's whereabouts. Can you solve the control room riddle and deactivate their weapon in time? Denni...

Your research team has found a prehistoric virus preserved in the permafrost and isolated it for study. After a late night working, you're just closing up the lab when a sudden earthquake hits and breaks all the sample vials. Will you be able to destroy the virus before the vents open and unleash a deadly airborne plague? Lisa Winer shows how. [...

The good news is that your experimental robo-ants are a success. The bad news is that you accidentally gave them the ability to shoot deadly lasers ... and you can't turn it off. Can you stop them from escaping their habitat before the lasers are activated? Dan Finkel shows how. [TED-Ed Animation by Artrake Studio].

Your rich, eccentric uncle just passed away, and you and your 99 nasty relatives have been invited to the reading of his will. He wanted to leave all of his money to you, but he knew that if he did, your relatives would pester you forever. Can you solve the riddle he left for you and get the inheritance? Lisa Winer shows how. [Directed by Artrak...

You've promised to get your son the cutest creature in creation: the cuddly. It's part of the Wuddly species, cousin to the terrifying duddly and the hideous fuddly. To make one, 100 eggs are placed in an incubator to undergo egg fusion, and the resulting combination will produce either a cuddly, a duddly or a fuddly. Can you make the right comb...

Your timing made you and your partner infamous bank robbers. Now, you need to use that timing to break out of jail. Your partner is about to flash you a signal, and exactly 45 seconds later the electric fence circuit will short out. Then you notice that your watch is broken, and all you have are two 1-minute fuses in your pocket. Can you time yo...

You're a biologist on a mission to keep the rare honeybee Apis Trifecta from going extinct. The last 60 bees of the species are in your terrarium. You've already constructed wire frames of the appropriate size and shape. Now you need to turn them into working beehives by filling every hex with wax. Can you help the bees create producing hives? D...

The villainous Dr. Schrödinger has developed a growth ray and intends to create an army of giant cats to terrorize the city. Your team of secret agents has tracked him to his underground lab. You burst in to find ... that it's a trap! Can you escape from Dr. Schrödinger's lair and save the day? Dan Finkel shows how. [TED-Ed Animation by Artrake ...

Smuggling yourself aboard the rogue submarine was the easy part. Hacking into the nuclear missile launch override — a little harder. And you've got a problem: you don't have the override code. You know you need the same numbers that were used to authorize the launch, but one wrong answer will lock you out. Can you figure out what numbers to ente...

Ragnarok: The fabled end of the world, when giants, monsters, and Norse gods battle for the future. The gods were winning until the great serpent Jörmungandr emerged. It swallowed Valhalla and contorted itself across the land. Odin has just enough power to strike with one final bolt of lightning, and you have the fabled hammer, Mjölnir. Can you ...

The night before the Death Race across the Wastelands is set to begin, your uncle, the great inventor Slate Kanoli, got kidnapped by the ruthless No-Side gang. The only way to get him back is to race his Coil Runner against the gang yourself. Win and they'll give back your uncle. Lose and you'll forfeit the Coil Runner and all his other creation...

A shooting star crashes onto Earth and a hideous blob emerges. It creeps and leaps, it glides and slides. It's also unstoppable: no matter what you throw at it, it just re-grows and continues its rampage. The only way to save the planet is to cut the entire blob into precise acute triangles while it sleeps, rendering it inert. Can you stop the b...

You're the realm's greatest mathematician, but ever since you criticized the Emperor's tax laws, you've been locked in the dungeon. Luckily for you, one of the Emperor's governors has been convicted of paying his taxes with a counterfeit coin, which has made its way into the treasury. Can you earn your freedom by finding the fake? Jennifer Lu sh...

It's an incredible discovery: an abandoned alien space station filled with precursor technology. Now every species in the galaxy is in a mad dash to get there first, but you've got a problem. Your ship can't hold enough fuel to get you there unless you vent caches of it into space at precise points and then come back for the fuel later. Can you ...

You and your best friend Bill are the greatest bards in the kingdom— but maybe not the brightest. Your hit song has insulted the king and now you're slated for execution. Luckily, Death is a connoisseur of most excellent music and has decided to give you a chance to escape your fate. Can you beat him at a game of life-sized Snakes and Ladders an...

Once a year, thousands of logicians descend into the desert for Learning Man. At the center of that gathering is the world's most exclusive club, where under the full moon the annual logician's rave takes place. The entry is guarded by the Demon of Reason, and the only way in is to solve one of his dastardly challenges. Can you get into the rave...

After years of war, the world's kingdoms have come to an agreement. Every five years, teams representing the elves, goblins, and treefolk will compete in a grand tournament of dragon jousting. You have the important job of recording the scores for the inaugural tournament. But, you overslept and the games are already underway. Can you figure out...

Someone has tripped the magical alarms in the Element Temple. When you and the other monks arrive on the scene, you know you have a disaster on your hands. Four young apprentices broke into the temple's inner chamber to steal the sacred element crystals. But when the alarm went off they panicked, and each of them swallowed a crystal. Can you det...

Professor Fukanō, the famous scientist, has embarked on a new challenge – piloting around the world in a plane of his own design. There's just one problem: there's not enough fuel to complete the journey. Luckily, there are two other planes to help. Can you help the professor fly for the whole trip and achieve his dream, without anyone running o...

Once every century, the world's greatest spiders gather to compete in a series of grueling games. The winner will become the next arachnomonarch, able to command all the world's spiders to their will. That day is today, and for the first time, you're casting your name into the ring. Can you attain the mantle of spider supremacy? Dan Finkel shows...

It was a normal Tuesday at the superconductor, until a bug in the system caused your team to be trapped in 11 separate dimensions. Fortunately, there's a half-finished experimental teleportation robot that may be able to get you all home... if you can figure out how to work it. Can you work out the robot's design quirks and get your team back ho...

One hundred green-eyed logicians have been imprisoned on an island by a mad dictator. Their only hope for freedom lies in the answer to one famously difficult logic puzzle. Can you solve it? Alex Gendler walks us through this green-eyed riddle. [Directed by Artrake Studio, narrated by Addison Anderson].

In a dystopian world, your resistance group is humanity's last hope. Unfortunately, you've all been captured by the tyrannical rulers and brought to the ancient coliseum for their deadly entertainment. Will you be able to solve the passcode riddle and get everyone out safely? Ganesh Pai shows how. [Directed by Jun Zee Myers, narrated by Addison ...

Your expedition finally stands at the heart of the ancient temple. But as you study the inscriptions in the darkness, two wisps of green smoke burst forth. The walls begin to shake. The giant sandglass begins flowing with less than an hour before it empties, and a rumbling tells you that you don't want to be around when that happens. Can you use...

Your professor has accidentally stepped through a time portal in his physics lab. You've got just a minute to jump through before it closes and leaves him stranded in history. Your only way back is to grab enough colored nodules to create a new portal to open a doorway through time. Can you take the right amount of nodules to get back to the pre...

It's your first day at Magnificent Marigold's Magical Macademy. But before you can learn your first spell you must get through the sorting ceremony. And the sorting hat has chosen you for a special challenge. The Macademy had 8 founders who established four houses, and there was once a mysterious fifth house. Can you figure out who founded what?...