Crash course biology

Crash course biology DEFAULT

Crash Course (YouTube)

Educational YouTube channel

For other uses, see Crash Course (disambiguation).

Crash Course (sometimes stylized as CrashCourse) is an educational YouTube channel started by John and Hank Green (collectively the Green brothers), who first achieved notability on the YouTube platform through their VlogBrothers channel.[1][2][3]

Crash Course was one of the hundred initial channels funded by YouTube's $ million original channel initiative. The channel launched a preview on December 2, , and as of January&#;[update], it has accumulated over 12 million subscribers and billion video views.[4] The channel launched with John and Hank presenting their respective World History and Biology series; the early history of the channel continued the trend of John and Hank presenting humanities and science courses, respectively.[5] In November , Hank announced a partnership with PBS Digital Studios, which would allow the channel to produce more courses. As a result, multiple additional hosts joined the show to increase the number of concurrent series.[citation needed]

To date, there are 44 main series of Crash Course, of which John has hosted nine and Hank has hosted seven. Together with Emily Graslie, they also co-hosted Big History. A second channel, Crash Course Kids, is hosted by Sabrina Cruz and has completed its first series, Science. The first foreign-language course, an Arabic reworking of the original World History series, is hosted by Yasser Abumuailek. The main channel has also begun a series of shorter animated episodes, called Recess, that focus on topics from the previous Crash Course series. A collaboration with Arizona State University titled Study Hall began in , which includes less structured learning in its topics.

Series overview[edit]

Main series[edit]

Series Episodes Series premiere Series finale Host(s) Writer(s)
Launched in
World History
World History 2
January 26,
July 11,
November 9,
April 4,
John GreenRaoul Meyer
Biology40 January 30, October 29, Hank Greenvarious
Ecology12 November 5, January 21, Hank GreenJesslyn Shields
English Literature
Literature 2
Literature 3
Literature 4
November 15,
February 27,
July 7,
November 7,
January 24,
June 12,
September 8,
February 13,
John GreenAlexis Soloski
Launched in
U.S. History48 January 31, February 6, John GreenRaoul Meyer
Chemistry46 February 11, January 13, Hank GreenKim Krieger
Launched in
Psychology40 February 3, November 24, Hank GreenKathleen Yale
Big History
Big History 2
September 17,
May 24,
January 9,
July 12,
Hank Green
John Green
Emily Graslie[n 2]
David Baker
Launched in
Anatomy & Physiology47 January 6, December 21, Hank GreenKathleen Yale
Astronomy46 January 15, January 21, Phil PlaitPhil Plait
U.S. Government and Politics50 January 23, March 4, Craig BenzineRaoul Meyer
Intellectual Property7 April 23, June 25, Stan Muller Raoul Meyer
Economics35 July 8, June 9, Adriene Hill
Jacob Clifford[n 3]
Patrick Walsh
Jacob Clifford
Scott Baumann
Launched in
Philosophy46 February 8, February 13, Hank GreenRuth Tallman
Physics46 March 31, March 24, Shini SomaraAlyssa Lerner
Games29 April 1, December 16, Andre Meadows Mathew Powers
Launched in
Computer Science40 February 22, December 21, Carrie Anne PhilbinAmy Ogan
Chris Harrison
World Mythology41 February 24, January 28, Mike Rugnetta Raoul Meyer
Sociology44 March 13, February 12, Nicole Sweeney Steven Lauterwasser
Film History
Film Production
Film Criticism
April 13,
August 24,
January 11,
August 3,
December 14,
April 26,
Craig Benzine
Lily Gladstone
Michael Aranda
Tobin Addington
Study Skills10 August 8, October 10, Thomas Frank Thomas Frank
Launched in
Statistics44 January 24, January 9, Adriene Hill Chelsea Parlett-Pelleriti
Theater50 February 9, March 1, Mike Rugnetta Alexis Soloski
Media Literacy12 February 27, May 15, Jay SmoothAubrey Nagle
History of Science46 March 26, April 29, Hank GreenWythe Marschall
Engineering46 May 17, May 2, Shini SomaraMichael Sago
Ricky Nathvani
Launched in
Navigating Digital Information10 January 8, March 12, John GreenAubrey Nagle
Business: Soft Skills
Business: Entrepreneurship
March 13,
August 14,
July 3,
December 11,
Evelyn Ngugi
Anna Akana
Rebecca Upton
Madeline Doering
European History50 April 12, August 28, John GreenBonnie Smith
Artificial Intelligence20 August 9, December 27, Jabril Ashe Lana Yarosh
Yonatan Bisk
Tim Weninger
Launched in
Organic Chemistry35[6]April 30, Deboki Chakravarti Kelley Donaghy
Kat Day
Andy Brunning
Kristen Procko
Linguistics16 September 11, January 22, Taylor Behnke Gretchen McCulloch
Lauren Gawne
Geography27[7]November 30, Alizé Carrère Alizé Carrère
Jane P. Gardner
Launched in
Zoology14 April 15, July 15, Rae Wynn-GrantBrittney G. Borowiec
Black American History19[8]May 7, Clint SmithClint Smith
Outbreak Science3[9]September 7, Pardis SabetiRicky Nathvani

Kids series[edit]

Foreign language series[edit]

Series Language Episodes Series premiere Series finale Host
World History[n 5]Arabic 42 January 19, July 5, Yasser Abumuailek


Series Episodes Series premiere Series finale
Recess2 March 5, October 2,
A History of Crash Course1 December 4,
How Crash Course is Made[n 6]6 March 22, April 10,
Covid and Public Health[n 7]1 October 19,
Crash Course Previews49 December 2, August 31st,

Study Hall series[edit]

A partnership with Arizona State University and hosted on their channel.

Series Episodes Series premiere Series finale Host
Composition15 April 1, July 7, Yumna Samie
Algebra15 April 23, July 30, James Tanton
Chemistry15 September 1, December 15, Will Comar
Data Literacy15 September 3, December 17, Jessica Pucci


In an interview with Entrepreneur, Crash Course producer and Sociology host Nicole Sweeney detailed:

Every year we have a big pitch meeting to determine what courses and things we're going to do the next year. In that meeting, we talk about a number of different things, but the rising question that motivates that meeting and then down the line as we're making decisions about what we're doing is what we think would be most useful for people.[10]

To make its content as useful as possible to viewers, the Crash Course channel hires experts relating to the topics of its series to work on the show.[11] The Missoula-filmed series are produced and edited by Nicholas Jenkins, while Blake de Pastino serves as script editor. The Indianapolis-filmed series is produced and edited by Stan Muller, Mark Olsen, and Brandon Brungard. Script editing is credited to Meredith Danko, Jason Weidner composes music for the series,[12] and Sweeney serves as a producer, editor, and director for Crash Course.[10] Raoul Meyer, an AP World History teacher and Green's former teacher at Indian Springs School, wrote the World History series, with John providing revisions and additions.[13] Sweeney has said that she and the respective host go over each script after it is edited to assess it for content.[10]

Sweeney also stated that each ten-minute episode takes about an hour to film.[10] The Philosophy series and all series relating to science (with the exception of Computer Science) were filmed in a studio building in Missoula, Montana that also houses SciShow.[14] The Biology and Ecology series were filmed in front of green screen, but from the Chemistry season onward, each series was filmed on new custom-built sets. The Computer Science series and all series on the humanities (excepting Philosophy and Economics) were filmed in a studio in Indianapolis, Indiana. In addition, Economics was filmed at the YouTube Space in Los Angeles, while Crash Course Kids was filmed in a studio in Toronto, Ontario. Crash Course Kids was directed by Michael Aranda and produced by the Missoula Crash Course team.

Once filmed, an episode goes through a preliminary edit before it is handed off to the channel's graphic contractor. Graphic design for all of the series except Biology and Ecology is provided by Thought Café (formerly Thought Bubble),[10] and the sound design and music for these series are provided by Michael Aranda (and in later series, his company Synema Studios.)

History and funding[edit]

YouTube-funded and Subbable periods (–)[edit]

Hank (left) and John Green (right) co-created Crash Courseand hosted the initial Biologyand World Historyseries, respectively.

The Crash Course YouTube channel was conceived by the Green Brothers after YouTube approached them with an opportunity to launch one of the initial YouTube-funded channels as part of the platform's original channel initiative.[15][16] The channel was teased in December ,[17] and then launched on January 26, , with the first episode of its World History series, hosted by John Green.[18] The episode covered the Agricultural Revolution, and a new episode aired on YouTube every Thursday through November 9, Hank Green's first series, Crash Course Biology, then launched on January 30, , with its first episode covering carbon. A new episode aired on YouTube every Monday until October 22 of that year. The brothers would then go on to end with two shorter series, with John and Hank teaching English literature and ecology, respectively.

Following their launch year, John and Hank returned in with U.S. History and Chemistry, respectively. However, that April, John detailed that Crash Course was going through financial hardships;[19] in July, Hank uploaded a video titled "A Chat with YouTube", in which he expressed his frustration with the ways YouTube had been changing and controlling its website.[20][21] Eventually, YouTube's original channel initiative funding ran out, and shortly after Hank's video, the Green brothers decided to launch Subbable, a crowdfunding website where viewers could donate monthly to channels in exchange for perks.[22] On launching Subbable, Hank Green stated: "We ascribe to the idealistic notion that audiences don't pay for things because they have to[,] but because they care about the stuff that they love and want it to continue to grow".[22]Crash Course was the first channel to be offered on Subbable, and for a time the website crowdfunded the channel.[23] In March , Subbable was acquired by Patreon, and Crash Course's crowdfunding moved over as part of the acquisition.

In May , John mentioned an upcoming episode Crash Course season on Big History, funded by a grant from one of Bill Gates' organizations.[24] The series outlined the history of existence, from the Big Bang forward into the evolution of life. Both Green brothers hosted the series, with Emily Graslie also participating as a guest host.[25]

Partnership with PBS Digital Studios (–)[edit]

In , Crash Course announced a partnership with PBS Digital Studios, which began in with the Astronomy and U.S. Government and Politics series.[26] In addition funding the channel itself, the partnership also entails PBS Digital Studios helping Crash Course to receive sponsorships.[10] As a result of the partnership as well as John commencing a year-long hiatus from the show in , additional hosts were added to increase the number of concurrent series. Though the partnership meant PBS Digital Studios would assist with the production of Crash Course, the channel continued to receive funding from its audience through Patreon.[27] In April , The Guardian reported that Crash Course received $25, per month through Patreon donations.[27] Aside from the new series on the main channel, Crash Course Kids was launched in February on a new Crash Course Kids channel.[28] The series was hosted by Sabrina Cruz, known on YouTube as NerdyAndQuirky.[29]

On October 12, , the Crash Course YouTube channel uploaded a preview for Crash Course Human Geography. Hosted by Miriam Nielsen, the course was to discuss "what Human Geography isn't, and what it is, and discuss humans in the context of their world." Two episodes were posted during each of the following two weeks; however, the videos were removed on October 27, with John Green stating on Twitter that "we got important things wrong. We'll rework the series And we'll bring a better series to you in a few months."[30] On October 31, John further explained that the videos were removed due to "factual mistakes as well as too strident a tone," and that the mishap was caused by a rushed production stemming from a lack of staffing and budgeting.[31] The following October, during an "Ask Me Anything" (AMA) session on Reddit, John indicated the course may not return for some time, noting that "we don't feel like we've cracked it yet."[32] The channel would go on to launch their Geography course in November , intended to cover both physical and human geography over its run.

In , Crash Course launched three film-related series: one covered film history, another film production, and the last of which covered film criticism.[33] Also in , Thomas Frank began hosting Crash Course Study Skills, which covered topics such as productivity skills, time management, and note-taking.[34]

Complexly branding and YouTube Learning Fund (–)[edit]

Anna Akana hosted Business: Entrepreneurshipin

Starting with the Statistics course in early , Crash Course series that are not PBS co-productions began to directly identify as Complexly productions. Also that year, Crash Course launched an Arabic-language edition of World History hosted by Yasser Abumuailek and produced by Deutsche Welle (DW), which was uploaded to DW's Arabic YouTube channel.[35] In July , YouTube announced its YouTube Learning initiative, dedicated to supporting educational content on the platform. A few months later, as $20 million was invested into expanding the initiative, Crash Course secured additional funding via the initiative's Learning Fund program.[36][37] However, PBS Digital Studios remained one of the primary sources of funding Crash Course, and the network also continued to help in finding sponsorships for the show.[10]

The channel surpassed 1 billion video views in February [38] In July, YouTube launched Learning Playlists as a continuation of their Learning Fund initiative;[39] while videos in Learning Playlists notably lack recommended videos attached to them, in contrast to videos included in regular playlists on YouTube,[39] they also include organizational features such as chapters around key concepts and lessons ordered by difficulty. After Learning Playlists' launch, Crash Course's video content was formatted into several of these playlists.[39] The channel reached 10 million subscribers in November [40]

Partnership with Arizona State University (–21)[edit]

A collaboration with Arizona State University (ASU) titled Study Hall was announced in March , which includes less structured learning in its topics. It was hosted by ASU alumni and advised by their faculty, with episodes posted on the university's YouTube channel but production and visual design by Complexly in the Crash Course style.[41]


Crash Course video series feature various formats depending on the host's presentation style as well as the subject of the course. However, throughout all series, the show's host will progressively elaborate on the topic(s) presented at the beginning of the video. Early on in the history of the show, the Green Brothers began to employ an edutainment style for episodes of Crash Course, using humor to blend entertainment together with the educational content.[42]

The World History series featured recurring segments such as the "Open Letter," where Green reads an open letter to a historical figure, period, item, or concept. Occasionally he converses with a naïve, younger version of himself whom he calls "Me from the Past"; this character usually has naïve or obvious questions or statements about the topic of the video.[5][43] A running joke throughout the series is that the Mongols are a major exception to most sweeping generalizations in world history, noted by the phrase "unless you are the Mongols". Mentions of this fact cue the "Mongoltage" (a portmanteau of "Mongol" and "montage"), which shows a drawing of Mongols shouting "We're the exception!" followed by a three-second clip of a scene from the film Hercules Against the Mongols depicting a village raid. Green also frequently encouraged his viewers to avoid looking at history through Eurocentric or "Great Man" lenses, but instead to be conscious of a broader historical context.

For U.S. History, Green followed the tone set by World History and put an emphasis on maintaining an open, non-Western view of American History. In addition, the "Open Letter" was replaced by a new segment called the "Mystery Document", in which Green would take a manuscript from the fireplace's secret compartment and read it aloud, followed by him guessing its author and the source work it is excerpted from. If incorrect, he would be punished by a shock pen. While the Mongoltage was largely absent, mentions of America's national pride during the series would cue a new "Libertage", which consisted of photos associated with America atop an American flag, with a guitar riff and an explosion at the start and end of the montage, respectively.

The Biology program featured the recurring segment "Biolo-graphy," during which Hank relayed a short biography of someone who was associated with the topic of the episode. Additionally, at the conclusion of each episode, Hank provided YouTube annotations with links to every subtopic he explained within the video. He also noted that the successor series to Biology, Crash Course Ecology, would follow in the spirit of the former series.[44]

Other releases[edit]

DVD box sets of the complete run of the Biology series and of season 1 of World History were made available for pre-order on October 31, [45] In June , the show's official site launched, providing free offline downloads of all episodes of every series completed to date.[46] In May , an official mobile app launched, providing easy access to all of the courses' video content along with rolling out flashcard and quiz study aides for particular courses.[47]


Overall, the Crash Course project has been successful in its reach, with World History alone having attracted millions of viewers.[48] It had a particular appeal to American students taking the AP World History class and exam; many students and teachers use the videos to supplement their courses.[2][49][50] In addition, various Crash Course episodes have been featured in online media publications.[51][52]

Awards and nominations[edit]


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  2. ^ abRoettgers, Janko (February 16, ). "A first look at YouTube's new TV stars". GigaOM. Archived from the original on January 17, Retrieved July 8,
  3. ^Leib, Bart (March 23, ). "Scishow & Crash Course: Why Isn't School This Cool?". Wired. Archived from the original on October 11, Retrieved July 8,
  4. ^"crashcourse YouTube Stats, Channel Statistics". Social Blade. Archived from the original on January 13, Retrieved January 14,
  5. ^ abTalbot, Margaret (June 9, ). "The Teen Whisperer". The New Yorker. Archived from the original on October 19, Retrieved October 20,
  6. ^Polymer Chemistry: Crash Course Organic Chemistry #35, retrieved
  7. ^Natural Hazards: Crash Course Geography #27, retrieved
  8. ^Reconstruction: Crash Course Black American History #19, retrieved
  9. ^Why Do We Have Fewer Outbreaks? Epidemiological Transition: Crash Course Outbreak Science #3, retrieved
  10. ^ abcdefgZipkin, Nina (November 7, ). "The Simple Question the Producers of the Wildly Popular 'Crash Course' Ask Themselves When Creating Content". Entrepreneur. Archived from the original on April 17, Retrieved August 31,
  11. ^Bernstein, Hannah (August 22, ). "Fake climate science videos have millions of views on YouTube. Here's what scientists can do about it". Ensia. Archived from the original on August 31, Retrieved August 31,
  12. ^ ab"Crash Course -- The Webby Awards". Webby Awards. Retrieved September 17,
  13. ^"History Teacher Discovers Talent As Educational Web Writer". Columbia Grammar & Preparatory School. November 5, Archived from the original on November 10, Retrieved February 7,
  14. ^Green, Hank (December 21, ). Meet the Team: The Missoula Office (And P4A and TheBrainScoop). Crash Course. YouTube. Archived from the original on March 22, Retrieved February 5,
  15. ^Roettgers, Janko (February 1, ). "Cool for school: Education is a big hit on YouTube". GigaOM. Archived from the original on February 9, Retrieved July 8,
  16. ^Gutelle, Sam (October 16, ). "Barack Obama Watches The Vlogbrothers". Tubefilter. Archived from the original on November 3, Retrieved October 23,
  17. ^Green, John (December 2, ). Crash Course Preview. Crash Course. YouTube. Archived from the original on April 12, Retrieved September 13,
  18. ^Higgins, Chris (February 9, ). "John Green's Crash Course in World History". mental_floss. Archived from the original on August 28, Retrieved July 8,
  19. ^Gutelle, Sam (April 2, ). "John Green Talks 'Crash Course', 'Hank Games', And Hats In Reddit IamA". Tubefilter. Archived from the original on December 5, Retrieved September 13,
  20. ^Gutelle, Sam (July 17, ). "Hank Green Is Pissed Off About YouTube's Constant Changes". Tubefilter. Archived from the original on October 10, Retrieved September 13,
  21. ^Green, Hank (July 17, ). A Chat with YouTube. hankschannel. YouTube. Archived from the original on December 3, Retrieved September 13,
  22. ^ abEifler, Emily (August 20, ). "Crowdfunding Matures with a Lesson from Public Broadcasting". Archived from the original on July 23, Retrieved November 30,
  23. ^Gutelle, Sam (July 22, ). "Vlogbrothers Launch Subbable, A 'Pay What You Want' Video Platform". Tubefilter. Archived from the original on August 22, Retrieved September 13,
  24. ^Green, John (May 20, ). Deserving. VlogBrothers. YouTube. Archived from the original on May 23, Retrieved May 22,
  25. ^"Big History Project - CrashCourse Videos". Big History Project. YouTube. Archived from the original on July 17, Retrieved September 7,
  26. ^Chmielewski, Dawn (November 7, ). "Vlogbrothers Bring "Crash Course" Videos to PBS Digital Studios". Recode. Archived from the original on March 3, Retrieved January 23,
  27. ^ abDredge, Stuart (April 8, ). "YouTube: Hank Green tells fellow creators to aim for '$1 per view'". The Guardian. Archived from the original on August 31, Retrieved August 31,
  28. ^Crash Course Kids Preview!. Crash Course Kids. YouTube. February 23, Archived from the original on January 17, Retrieved August 31,
  29. ^Lanning, Carly (September 16, ). "#WCW Sabrina Cruz is the queen of the nerds". The Daily Dot. Archived from the original on August 31, Retrieved August 31,
  30. ^@johngreen (October 27, ). "We're taking down the first two Crash Course Human Geography videos" (Tweet) &#; via Twitter.
  31. ^Green, John (October 31, ). A Note on CC Human Geography. Crash Course. YouTube. Archived from the original on November 25, Retrieved October 31,
  32. ^Green, John. "I'm John Green, author of The Fault in Our Stars and Turtles All the Way Down. I'm in a bus for the next eight hours. AMA". Reddit. Retrieved October 17,
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  1. ^as of October 5th
  2. ^Graslie is the sole host of the second season.
  3. ^Clifford departed after the 29th episode, with Hill presenting the remainder solo.
  4. ^Hosted on the Crash Course Kids channel.
  5. ^Hosted on the DW عربية channel.
  6. ^A partnership with Adobe and hosted on the Thought Café channel.
  7. ^A partnership with Operation Outbreak and the Sabeti Lab at Harvard.

External links[edit]


Hank describes why plants are so freaking amazing - discussing their evolution, and how their cells are both similar to & different from animal cells. Created by Crash Course.

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Unable to bear the. Beauty of the unfolding picture, Lieutenant Edward ran up to Nonka, grabbed her by the head, raised her and at eye level, she saw his intricate and crimson penis, which pinched into her blood-red mouth. He smeared lipstick on his lips with his head, stuck his cock into his mouth and suddenly took it out to beat it on the. Cheeks and lips.

Then he dipped it into a glass of whiskey and let Nonka lick the spicy moisture.

Biology crash course

And when my dad arrived, my colleagues were happy to "help out" me, only demanding, impudent, that I ask them about it "well", they say they are not libertines who. Seduced me, but simply "weak women. " As the mummy whispered sarcastically "weak for all the holes", just have time to ask. Oh, this is female malice. But unfortunately, all the miraculous ends soon in May, I received a summons to our legendary and invincible army.

Plant Cells: Crash Course Biology #6

He returned to. The room where he slept. I lay down on the sofa.

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He led her into a large room and allowed her to get to her feet. He walked around her, stroking her tummy. He led her over to the couch and threw her over the armrest.

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