• BHP Lesson 20: Darwin’s Theory of Natural Selection

    Life first appeared on Earth about 3.8 billion years ago. How is it possible for scientists to know about the history of life? What methods do they use to study life and the ways it has evolved over time? Today, we’ll take a closer look at the pioneer of life history—Charles Darwin.

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    Driving Question: How did Darwin arrive at his theory of natural selection?

    • Perhaps you’ve heard the phrase…
  • BHP Lesson 19: The Extinction of the Dinosaurs

    An asteroid killed the dinosaurs. Or did it? Today we’ll investigate several competing theories about the extinction event that wiped out T-Rex and friends.

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    Driving Question: How can we prove an asteroid wiped out the dinosaurs?

    • We’ve got a scientific murder mystery on our hands today. Here’s what we know. 66 million years ago, three pretty colossal events occurred: 1) 75% of all plant…
  • BHP Lesson 18: Biospheres: Our Habitat

    The biosphere is an amazing place, serving as the home for all the living things on our planet. It provides us with air to breathe, plus plants, animals, and water to survive. We live in the comfort zone, but what would happen if we were pushed to the extremes of the biosphere? We’ll explore that question today with Alphonse the camel.

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    Driving Question: How do Earth and life interact?

    • BHP Lesson 17: The Beginning of Life on Earth

      How did life begin? Some scientists argue it started in shallow pools of water, while others maintain that it began deep below the surface of the ocean. Still others believe that a meteor from some distant corner of the Universe brought the ingredients necessary for life to Earth. How life appeared might be the most interesting question we tackle in this course!

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      Driving Question: How did life…

    • BHP Lesson 16: What is Life?

      Biologists, the leading experts on life, struggle to agree upon a definition for this simple question. Today, we’re going to talk about what life is... and what it isn’t. By the end, we’ll settle on a definition even the biologists would be proud of! Today you’ll also get to meet our class forest family. Please make an effort to learn all of their names.

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      Driving Question…

    • BHP Lesson 15: How Theories Become Accepted

      To explain something they observe, scientists often begin with a hypothesis—their best guess about why and how it occurs. Sometimes a new hypothesis generates a lot of controversy, especially in the early stages of being tested. A central question in both the history of science and our everyday lives is when should people accept new ideas? Plate tectonics provides a great case study. The original theory met stiff resistance…

    • BHP Lesson 14: Plate Tectonics

      The surface of the Earth is changing all the time. We’re really all just lava surfers, and we’ve been riding the lava waves for a long time. In fact, it’s now possible for scientists to determine how the tectonic plates on the surface of the Earth have moved over time—which is good news for us historians! We can use that scientific information to write the history of the Earth. 

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    • BHP Lesson 13: The Formation of Earth & the Solar System

      Leftovers usually aren’t that interesting or important, but the leftovers that circled our Sun just after its birth are another story. Gravity helped to separate that matter by density, forming all the different planets in our solar system. Our own planet, Earth, was uniquely positioned at just the right distance from the Sun and composed of diverse elements. But early Earth was very different from the world we know today…

    • BHP Lesson 12: The Periodic Table

      Chemistry plays an important role in Big History. The elements born out of the death of stars are what connect our world today with the stars, their death, and the birth of the Universe. The world around us today is an ode to chemistry and one chemist in particular, Dmitri Mendeleev. Inspired by a simple game of solitaire, Mendeleev found a brilliant new way to organize the elements into the periodic table we know today…

    • BHP Lesson 11: The Formation of Stars & Elements

      By 200 million years after the Big Bang, the Universe had become a very dark and cold place. Then things started to change. First, dust and gas formed. Then stars emerged from these clouds of dust and gas. Those early stars led short lives and produced many of the chemical elements of the periodic table in their deaths. Today you’ll learn how stars first formed and how their deaths provided the chemical diversity necessary…

    • BHP Lesson 10: Evidence

      One of the most powerful claim testers we have at our disposal in search of the truth is evidence. It’s hard to ignore the kind of facts that you can see and verify. That’s why evidence is so strongly tied to belief. In this episode, we’ll take a look at the evidence behind the Big Bang theory and put it to the test.

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      Driving Question: How does evidence help us decide what to believe…

    • BHP Lesson 9: Authority

      Authority is one of the claim testers that helps us decide what to believe. People who are experts gain credibility in their field by consistently demonstrating logical and reliable patterns of thinking. In this video, we’ll examine those qualities we find most trustworthy in experts.

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      Driving Question: Who should we trust when seeking new knowledge?

      • When experts weigh in on a topic, our ears…
    • BHP Lesson 8: Claim Testing

      In Big History, students are presented with a lot of claims. We use the term “claim testing” in Big History to describe the process that someone goes through when evaluating the credibility of an assertion. In an age when we are inundated with new claims by the second, it’s important that we have a process for deciding what to believe and who to trust—and what warrants further investigation. Alphonse the Camel returns…

    • BHP Lesson 7: The Big Bang

      The Big Bang remains a mystery in many ways. We have a lot of evidence for what happened just after, but we can only guess at what existed before. Observing the Universe tells us a lot about the Big Bang, yet scientists are still searching for more answers.

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      Driving Question: What evidence supports the Big Bang theory?

      • Last week, we talked about where everything came from, and today, we’re going…
    • BHP Lesson 6: Changing Views of the Universe

      The Big Bang hasn’t always been the generally accepted explanation of how our Universe came to be. In fact, our views on the origin and structure of the Universe have changed drastically over the last thousand years. As new thinking and evidence have built upon one another, our understanding has evolved.

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      Driving Question: How and why did our understanding of the Universe change over time?

      • BHP Lesson 5: Complexity

        As the planet has evolved since the beginning of time, everything, including plants, humans, and animals, have gotten more complicated. In Big History, we break up time, or periodize, by using major changes in complexity as markers for these changes. We call these turning points thresholds of increasing complexity.

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        Driving Question: How did complexity get us to where we are now?

        • Think about the…
      • BHP Lesson 4: What Are Disciplines?

        History relies on way more than just historians to put together accounts of the past. Archeologists, anthropologists, physicists, cosmologists, and many, many others contribute to our understanding of history. In this video, we’ll consider how these different disciplines and perspectives give us a richer understanding of the past, and our world today.

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        Driving Question: How can looking at the…

      • BHP Lesson 3: Origin Stories

        Everything came from somewhere. In this video, we’ll consider those somewheres, and the stories we tell to explain and understand how life, the universe, and everything came to be. You’ll also meet Alphonse the Camel, who is co-hosting today’s video.

        https://youtu.be/a8yOglDgQEg

        Driving Question: Where did everything come from?

        • Every culture has a story they tell about the Universe, its origin, and…
      • BHP Lesson 2: Scale

        Today, we’ll learn about the importance of scale when studying history. We’ll think about scales of both time and space, and how they impact our understanding of the past.

        www.youtube.com/watch

        Driving Question: Why do we look at things from up close and far away?

        • Have you ever looked at something from a great distance, such as from a mountaintop or an airplane, and then looked at the same thing up close…
      • BHP Lesson 1: Welcome to Big History

        This video introduces the Big History Project course on Khan Academy, and your host, Rachel Hansen. You’ll be given a driving question to explore, a word of the day to think about, and video to watch. Finally, you’ll make your first entry in your historian’s journal.

        https://youtu.be/M2c8bAQHT0g

        Driving Question: What is Big History?

        • Big History is probably a bit different than any other history course…