Being able to use human feces as fertilizer could be really helpful for human colonies on other planets. It could also be useful for human colonies on THIS planet! And who doesn’t love recycling!?

In this video Paul Andersen explains how systems can be used to understand phenomenon in science and create better designs in engineering. He starts by defining the characteristics of a system and describes how system models can be used...

If you’ve got a job interview coming up and you’re feeling a little nervous, don’t worry. If you’re anything like me, you’ve probably seen enough celebrity interviews to know what works and what doesn’t. Sure, it's not as flashy, but you...

Squeaks and Mister Brown are so excited about rockets, they're going to make their own! You can join in on the fun and learn how to make one too!

In this video Paul Andersen explains how the reaction quotient is used to determine the progress of a reversible reaction. The reaction quotient (Q) is the ratio of the concentration of products to the concentration of reactants. The...

Why is it that humans react to stimuli with certain behaviors? Can behaviors change in response to consequences? Peggy Andover explains how the brain can associate unrelated stimuli and responses, proved by Ivan Pavlov's famous 1890...

When it comes to sex things can be complicated, but for the three species we are looking at today, sex is really hard.

It's the end of this first year of Crash Course Kids and we've learned so many things. In this episode, Sabrina takes us on a tour of some of the ideas we've talked about and how they fit into our lives. Also, what all of these ideas...

The bottom of the cereal box is a disappointing place. But at least now you know why. Where do you see the Brazil Nut Effect around you?

Me, myself, and I. You may be tempted to use these words interchangeably, because they all refer to the same thing. But in fact, each one has a specific role in a sentence: 'I' is a subject pronoun, 'me' is an object pronoun, and...

Paul Andersen explains the central dogma of biology. He explains how genes in the DNA are converted to mRNA through the process of transcription. He then explains how ribosomes use this message to convert the mRNA to a functioning...

In this video Paul Andersen explains how the atomic model has changed over time. A model is simply a theoretical construct of phenomenon and so when we receive new data we may have to refine our model. Ionization energy data resulted...

Paul Andersen gives ten tips on increasing comprehension.

Was da Vinci an artistic genius? Sure, but he was also born in the right place at the right time -- pre-Renaissance, Western artists got little individual credit for their work. And in many non-Western cultures, traditional forms have...

Scientists know that anesthesia drugs are really good at knocking you out. What they don't know is how.

Paul Andersen describes the process of mitosis. He begins by discussing the importance of the cell cycle in development, regeneration, asexual reproduction and wound healing. He differentiates between haploid and diploid cells and...

We need to think beyond national borders to solve global problems, says activist Colombe Cahen-Salvador. Reimagining the world's fractured systems of governance and calling out their ineffective responses to major issues -- from the...

In this video Paul Andersen outlines the AP Environmental Science course. He explains how environmental science studies the interaction between earth and human systems. A planetary boundary model is used to explain the importance of...

In which a series about literature, which is wanting of an episode on Jane Austen, gets the first of two episodes. It's Pride and Prejudice, everybody! John Green talks about Pride and Prejudice as a product of Regency England, gives you...

Why, why, why does our education system look so similar to the way it did 50 years ago? Millions of students were failing then, as they are now -- and it’s because we’re clinging to a business model that clearly doesn’t work. Education...

This week, Stan Muller teaches you the basics of copyright in the United States. Copyright law is territorial, so we're going to cover the system we know the most about, and that's the US. Stan will talk about what kind of ideas can be...

Stan Muller teaches you a few things about copyright enforcement, and talks about the exceptions to copyright enforcement. While there are several, the one you've probably heard of is Fair Use, and it's a pretty tricky one. We'll try to...

Thelma Golden, curator at the Studio Museum in Harlem, talks through three recent shows that explore how art examines and redefines culture. The "post-black" artists she works with are using their art to provoke a new dialogue about race...

There's not a lot of tried and true ways to get a rowdy classroom in control, with the exception of the Good Behavior Game. But there's one big caveat as to who it helps.