Look to your left. Look to your right. Look at this video. Today, John Green is going to teach you how to read laterally, using multiple tabs in your browser to look stuff up and fact check as you read. Real-time fact-checking an help you figure out what's real and what's not on the internet.

Cells need energy to power the chemical reactions that keep their microscopic cities running, and most of that energy comes from a chemical called ATP. In this episode of Crash Course Biology, we’ll learn how our cells use energy, what an enzyme’s role is in chemical reactions, and what makes a reaction exergonic or endergonic.

Chapters:
Cellular Cities
What Is Energy?
The Laws of Thermodynamics
ATP
Chemical Reactions
Enzymes
Metabolic Pathways
Review & Credits
Credits

Things have been getting more and more complicated here in Crash Course Organic Chemistry, and as we deal with more complex molecules, parts of molecules we don’t want to react will start reacting along with the parts that we do. Luckily, we have protecting groups, which act like a chemical disguise and help us control how molecules react. In this episode, we’ll look at what makes a good protecting group, as well as identify some good protecting groups for different functional groups. We’ll also see what role protecting groups play in the synthesis of penicillin!

Today we're going to talk about Chi-Square Tests - which allow us to measure differences in strictly categorical data like hair color, dog breed, or academic degree. We'll cover the three main Chi-Square tests: goodness of fit test, test of independence, and test of homogeneity. And explain how we can use each of these tests to make comparisons.

This week we're headed to China to learn about the ancient origins of theater there. We'll look at the early days of wizard theater (not a typo), the development of classical Chinese theater, and the evolution of Beijing Opera.

Now that we have a better grasp on chosing majors, let's talk a little about specializations. There's a lot to talk about, from declaring a minor to just taking electives that help you get an edge in the job market. And how do you find out what classes may help in the job market? Erica walks us through ways to find this out and how to think about specialization in your college journey!

Chapters:
- Introduction
- Balancing your schedule
- Preparing for your meeting
- Your goals
- Supplementing your degree with more experience
- Conclusion

Review

Hank introduces us to ourselves by taking us on a journey through the fascinatingly diverse phyla known as chordata. And the next time someone asks you who you are, you can give them the facts: you're a mammalian amniotic tetrapodal sarcopterygian osteichthyen gnathostomal vertebrate cranial chordate.

Chapters:
1) Chordate Synapomorphies
2) Cephalachordata
3) Urochordata
4) Vertebrata
a) Myxini
b) Petromyzontida
c) Chondrichthyes
d) Osteichthyes
5) Biolography
6) Amphibia
7) Reptilia
8) Mammalia

In which John Green teaches you the history of Christianity, from the beginnings of Judaism and the development of monotheism, right up to Paul and how Christianity stormed the Roman Empire in just a few hundred years. Along the way, John will cover Abram/Abraham, the Covenant, the Roman Occupation of Judea, and the birth, life, death, and legacy of Jesus of Nazareth. No flame wars! Let's keep the commentary civil.

Chapters:
Introduction: The Son of God
Understanding the Jewish Tradition
Herod and Herod - Roman Rulers
Jesus of Nazareth
Why did people believe Jesus was the Messiah?
Why was Jesus so influential?
Saul / Paul of Tarsus
An Open Letter to The Fish (Ichthys)
How Christianity Survived
Credits

How does Stranger Things fit in with physics and, more specifically, circuit analysis? I'm glad you asked! In this episode of Crash Course Physics, Shini walks us through the differences between series and parallel circuits and how that makes Christmas lights work the way they work.

Hank takes us on a trip around the body - we follow the circulatory and respiratory systems as they deliver oxygen and remove carbon dioxide from cells, and help make it possible for our bodies to function.

Chapters:
1) Respiratory System
2) Simple Diffusion
3) Respiratory Anatomy
a) Trachea to Capillaries
4) Lung Function & Thoracic Diaphragm
5) Circulatory System
6) Circulatory Anatomy
a) Left Ventricle to Capillary Beds
b) Veins to Left Atrium
7) Endotherms & Ectotherms

This week on Crash Course Mythology, we're getting urban. Mike Rugnetta is the man with the orange umbrella who's about to give you a free tour of mythical cities. We'll talk about a few cities that didn't exist, but we're going to focus on real cities with mythical founding stories. We'll talk about Jericho, Jerusalem, and Rome, among others.

We’re beginning our engineering journey with a tour through the major branches. Today Shini explains the facets of civil engineering, including structural and construction engineering, city planning, transportation, and sanitation.

Today, Craig is going to give you an overview of civil rights and civil liberties. Often these terms are used interchangeably, but they are actually very different. Our civil liberties, contained in the Bill of Rights, once only protected us from the federal government, but slowly these liberties have been incorporated to protect us from the states. We’ll take a look at how this has happened and the supreme court cases that got us here.

In which John Green teaches you about the early days of the Civil Rights movement. By way of providing context for this, John also talks a bit about wider America in the 1950s. The 1950s are a deeply nostalgic period for many Americans, but there is more than a little idealizing going on here. The 1950s were a time of economic expansion, new technologies, and a growing middle class. America was becoming a suburban nation thanks to cookie-cutter housing developments like the Levittowns. While the white working-class saw their wages and status improve, the proverbial rising tide wasn't lifting all proverbial ships. A lot of people were excluded from the prosperity of the 1950s. Segregation in housing and education made for some serious inequality for African Americans. As a result, the Civil Rights movement was born. John will talk about the early careers of Martin Luther King, Thurgood Marshall, Rosa Parks, and even Earl Warren. He'll teach you about Brown v Board of Education, the lesser-known Mendez vs Westminster, the Montgomery Bus Boycott, and all kinds of other stuff.

Chapters:
Introduction: The 1950s
The American Suburbs
The "Era of Consensus"
Segregation
Desegregating Schools
Mystery Document
The Aftermath of Brown vs. Board of Education
Rosa Parks & the Montgomery Bus Boycotts
Martin Luther King, Jr.
The Little Rock Nine
The Emergence of the Civil Rights Movement
Credits

In which John Green teaches you how the Civil War played a large part in making the United States the country that it is today. He covers some of the key ways in which Abraham Lincoln influenced the outcome of the war, and how the lack of foreign intervention also helped the Union win the war. John also covers the technology that made the Civil War different than previous wars. New weapons helped to influence the outcomes of battles, but photography influenced how the public at large perceived the war. In addition, John gets into the long-term effects of the war, including the federalization and unification of the United States. All this plus homesteading, land grant universities, railroads, federal currency, and taxes.

Chapters:
Introduction
Did Lincoln Free the Slaves?
How Some Slaves Freed Themselves
Why Lincoln Signed the Emancipation Proclamation
The Gettysburg Address
The First Modern War
Mystery Document
Matthew Brady - Civil War Photographer
A New Nation
The Homestead Act, Morrill Land Grant Act, and Pacific Railway Act
Financing the Civil War
Post-War Industrialization
Credits

In which John Green ACTUALLY teaches about the Civil War. In part one of our two-part look at the US Civil War, John looks into the causes of the war, and the motivations of the individuals who went to war. The overarching causes and the individual motivations were not always the same, you see. John also looks into why the North won, and whether that outcome was inevitable. The North's industrial and population advantages are examined, as are the problems of the Confederacy, including its need to build a nation at the same time it was fighting a war. As usual, John doesn't get much into the actual battle-by-battle breakdown. He does talk a little about the overarching strategy that won the war, and Grant's plan to just overwhelm the South with numbers. Grant took a lot of losses in the latter days of the war, but in the end, it did lead to the surrender of the South.

Chapters:
Introduction
Basic Facts of the Civil War
Free and Slave States
Causes of the Civil War
Religion and the Civil War
Union Advantages in the Civil War
Confederate Advantages in the Civil War
Was the Union's Victory Inevitable?
Mystery Document
Ulysses S. Grant
Union Weaknesses in the Civil War
Turning Points in the Civil War
Lincoln's Reelection
Credits

The architecture of the social internet itself tells us not to be patient - to load more tweets, to hit refresh for new posts, and to click the top search results. But just because information is new, or algorithmically determined to be most relevant to you, doesn't necessarily mean it's the best or most accurate. So today we're going to teach you some tips to exercise a little more click restraint on the Internet.

In which John Green teaches you about the Little Ice Age. The Little Ice Age was a period of global cooling that occurred from the 13th to the 19th centuries. This cooling was likely caused by a number of factors, including unusual solar activity and volcanic eruptions. The Little Ice Age greatly impacted human social orders, especially during the 17th century. When the climate changed, and the weather became unpredictable, the world changed profoundly. Poor harvests led to hunger, which led to even less productivity, which even resulted in violent upheaval in a lot of places. All this from a little change in the temperature? Definitely.

In which John Green teaches you about the United States as it was in the 1990s. You'll remember from last week that the old-school Republican George H.W. Bush had lost the 1992 presidential election to a young upstart Democrat from Arkansas named Bill Clinton. Clinton was a bit of a dark horse candidate, having survived a sex scandal during the election, but a third-party run by Ross Perot split the vote, and Clinton was inaugurated in 1993. John will teach you about Clinton's foreign policy agenda, which included NATO action in the Balkans and the Oslo Accords between Israel and the PLO. He'll also cover some of the domestic successes and failures of the Clinton years, including the failed attempt at healthcare reform, the pretty terrible record on GLBTQ issues, Welfare reform, which got mixed reviews, and the happier issues like the huge improvements in the economy. Also computers. Cheap, effective, readily available computers came along in the 1990s, and they kind of changed the world, culminating in this video, which is the end of the internet. Until next week.

Chapters:
Introduction: The Clinton Years
Clinton's Foreign Policy
Terrorism During the Clinton Era
Clinton's Domestic Policy
Clinton's Triangulation Strategy
Clinton's Welfare Reforms
Economics During the Clinton Era
The E-Commerce Boom
Mystery Document
Globalization of Manufacturing, Technology, and Commerce
The Crash of 2000
Increasing Wealth Inequality
The Culture Wars
An Influx of Immigration
Diverse Family Structures
The AIDS Epidemic & LGBT Rights Movement
Imprisonment & the "War on Drugs"
Multiculturalism & Political Tensions
Clinton's Infidelity & Impeachment
Clinton's Legacy
Credits

In which John Green wraps up revolutions month with what is arguably the most revolutionary of modern revolutions, the Industrial Revolution. While very few leaders were beheaded in the course of this one, it changed the lives of more people more dramatically than any of the political revolutions we've discussed. So, why did the Industrial Revolution happen around 1750 in the United Kingdom? Coal. Easily accessible coal, it turns out. All this, plus you'll finally learn the difference between James Watt and Thomas Newcomen, and will never again be caught telling people that your blender has a 900 Newcomen motor.

Chapters:
Introduction: The Industrial Revolution
What Was the Industrial Revolution?
Innovations in the British Textile Industry
Why did the Industrial Revolution start in Europe?
An Open Letter to the Steam Engine
What was going on in China during the Industrial Revolution?
European Advantages: High Wages and Low Fuel Costs
What was going on in India during the Industrial Revolution?
Credits