If you are a TED-Ed community member who waits with anticipation for new TED-Ed Original videos to be published, then you’ll likely enjoy a few fun facts about the curiosity-inspired educational videos that were published three times a week in 2015. For example, did  you know that TED-Ed works with hundreds of talented animators and brilliant educators from around the globe to produce these 3-5 minute short videos? Or that there’s a small but mighty group of about 10 people who work on each and every TED-Ed Original, from editing to writing to fact checking to reviewing all animations? Or that in total, the TED-Ed audience has watched more than 344,071,325 minutes of TED-Ed original video content this year? That’s nearly 240,000 days, or 654 years of watching! As a thank you to our audience as we approach the end of 2015, here’s a list of the top 10 most popular TED-Ed Originals of 2015:

1. Can you solve the bridge riddle?

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 the zombies arrive? Alex Gendler shows how. Watch this TED-Ed Original below.

2. Can you solve the prisoner hat riddle?

You and nine other individuals have been captured by super-intelligent alien overlords. The aliens think humans look quite tasty, but their civilization forbids eating highly logical and cooperative beings. Unfortunately, they’re not sure whether you qualify, so they decide to give you all a test. Can you solve this hat riddle? Alex Gendler shows how. Watch this TED-Ed Original below.

3. Why sitting is bad for you

Sitting down for brief periods can help us recover from stress or recuperate from exercise. But nowadays, our lifestyles make us sit much more than we move around. Are our bodies built for such a sedentary existence? Murat Dalkilinç investigates the hidden risks of sitting down. Watch this TED-Ed Original below.

4. The famously difficult green-eyed logic puzzle

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. Watch this TED-Ed Original below.

5. The wars that inspired Game of Thrones

Beginning around 1377, medieval England was shaken by a power struggle between two noble families, which spanned generations and involved a massive cast of characters, complex motives and shifting loyalties. Sound familiar? Alex Gendler illustrates how the historical conflict known as the Wars of the Roses served as the basis for much of the drama in Game of Thrones. Watch this TED-Ed Original below.

6. What would happen if you didn’t sleep?

In the United States, it’s estimated that 30 percent of adults and 66 percent of adolescents are regularly sleep-deprived. This isn’t just a minor inconvenience: staying awake can cause serious bodily harm. Claudia Aguirre shows what happens to your body and brain when you skip sleep. Watch this TED-Ed Original below.

7. Why are some people left-handed?

Today, about one-tenth of the world’s population are southpaws. Why are such a small proportion of people left-handed — and why does the trait exist in the first place? Daniel M. Abrams investigates how the uneven ratio of lefties and righties gives insight into a balance between competitive and cooperative pressures on human evolution. Watch this TED-Ed Original below.

8. The benefits of good posture

Has anyone ever told you, “Stand up straight!” or scolded you for slouching at a family dinner? Comments like that might be annoying — but they’re not wrong. Your posture is the foundation for every movement your body makes and can determine how well your body adapts to the stresses on it. Murat Dalkilinç gives the pros of good posture. Watch this TED-Ed Original below.

9. How do dogs “see” with their noses?

You may have heard the expression that dogs ‘see with their noses.’ But these creature’s amazing nasal architecture actually reveals a whole world beyond what we can see. Alexandra Horowitz illustrates how the dog’s nose can smell the past, the future and even things that can’t be seen at all. Watch this TED-Ed Original below.

10. What makes muscles grow?

We have over 600 muscles in our bodies that help bind us together, hold us up, and help us move. Your muscles also need your constant attention, because the way you treat them on a daily basis determines whether they will wither or grow. Jeffrey Siegel illustrates how a good mix of sleep, nutrition and exercise keep your muscles as big and strong as possible. Watch this TED-Ed Original below.

So what have we discovered about the TED-Ed audience in 2015? It seems that we all like stretching our minds — especially with riddles. We all like knowing about our bodies, and how they work. And, most importantly, we all love to learn.

On behalf of everyone here at TED-Ed, thanks for learning with us this year!

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