Imagine something small enough to float on a particle of dust that holds the keys to understanding cancer, virology, and genetics. Luckily for us, such a thing exists in the form of trillions upon trillions of human, lab-grown cells called HeLa. But where did we get these cells? Robin Bulleri tells the story of Henrietta Lacks, a woman whose DNA led to countless cures, patents, and discoveries. [4:26]

Video that describes the types of codes that media and advertisements use to affect the way that people think, act, and feel. [6:00] Followed by a short quiz and a list of additional resources to explore.

What can mathematics say about history? From changes to language to the deadliness of wars, Jean-Baptiste Michel shows how digitized history is just starting to reveal deep underlying patterns. [4:26]

Cells are almost like tiny factories run by robots, with the nucleus, DNA, proteins, lipids, and vitamins and minerals all playing critical roles. George Zaidan and Charles Morton lay out the blueprint of a cell and explain how biochemistry binds all life together. [4:01]

Among the great poets of literary history, certain names like Homer, Shakespeare and Whitman are instantly recognizable. However, there's an early 20th century great poet whose name you may not know: Guillaume Apollinaire. Genevieve Emy shows how during Apollinaire's short lifetime he created poetry that combined text and image in a way that seemingly predicted a artistic revolution to come. [4:15]

A fun, playful introduction to using short, simple words when attempting to communicate a point of information. [2:02] W.9-10.2d lang/voc

Never underestimate the power of an intriguing start. When analyzing the literary greats like Charles Dickens and Kurt Vonnegut, be inspired by their craft and learn how to write a tantalizing introduction and strong thesis. Free registration is required for full access to the lesson.

Often people make decisions that are not "rational" from a purely economical point of view. Sara Garofalo explains heuristics, problem-solving approaches based on previous experience and intuition rather than analysis. [4:39]

Fighting plagiarism is serious business. From brainchild-snatching to wholly quotables, plagiarists have plenty of wily ways to pass others' work off as their own- and all of them are threats to original thinking. Melissa Huseman D'Annunzio imagines what would happen if a Department of Plagiarism Investigation were on the case. [3:48]

Brute computing force alone can't solve the world's problems. Data mining innovator Shyam Sankar explains why solving big problems is not a question of finding the right algorithm, but rather the right symbiotic relationship between computation and human creativity. [12:13]

To understand how hearing works, Douglas L. Oliver follows a sound on its journey into the ear. [5:17]

Colm Kelleher unpacks symmetry and explains how animals' distinct symmetries can tell us more about them- and ourselves. [5:09]

Learn about the process of photosynthesis and how it is related to the food we eat. [4:01]

Suppose you placed a camera at a fixed position, took a picture of the sky at the same time every day for an entire year, and overlaid all of the photos on top of each other. What would the sun look like in that combined image? A stationary dot? A circular path? Neither. Oddly enough, it makes a 'figure 8' pattern, known as the Sun's analemma. Gordon Williamson explains why. [4:23]

This lesson illustrates the hidden truths behind what really motivates us at home and in the workplace. You'll be surprised, no doubt- but watch out! You might find that your motivations are misplaced. [10:48]

We've all heard the phrase "Time is money." But what do these two things actually have to do with one another? German Nande explains the math behind interest rates, revealing the equation that will allow you to calculate the future value of your money (if you wisely put it in the bank, that is). [3:36]

Seth Godin argues the Internet has ended mass marketing and revived a human social unit from the distant past: tribes. Founded on shared ideas and values, tribes give ordinary people the power to lead and make big change. He urges us to do so. [17:27]

William Ury, author of "Getting to Yes," offers an elegant, simple way to create agreement in even the most difficult situations-from family conflict to, perhaps, the Middle East. [18:45]