Smilodon's fangs averaged 18 cm long. An engaging video explains what saberteeth are and how they evolved. It details the theories about how species used saberteeth and why cats don't have them today. 

No two are ever alike, so they say. Young scientists view an engaging video in a playlist series to learn about snowflakes. They see how snowflakes form and study several different categories of them.

Light up some interest in matches. An illuminating video shows a slow motion clip of a match being lit. It describes the ingredients and the chemistry behind matches.

What is your favorite crystal? Scholars learn about the variety of different crystal in an episode of a video series on chemical reactions. The video presents intriguing facts about these crystals that make each unique—a fun approach to...

Your heart may not be pumping, but there are still many chemical reactions that continue in your body. An installment of a video series on chemical reactions describes the decomposition process of our bodies after death. It pays...

Discover the transition from circular orbit theories to elliptical orbits. An episode of a video series on astronomy models the different elliptical shapes of the orbits of the planets in the solar systems. Using string, the presenter...

Time does not exist as a universal constant, yet it can be defined as a concrete reality. These concepts and more provide the inspiration for an episode of Space Time's larger series of the same name. It discusses causal order, the...

Dimetrodon lived before flowers, and people often believe it was a dinosaur. Research, however, proves a different story. An informative video teaches more about the dimetrodon, a mammal often confused for a reptile. It explains the...

How do scientists define a mass extinction event in the fossil record, and what happens when they are wrong? Scientists find living plants and animals previously believed to be extinct on almost every continent. An engaging video...

At one point, scale trees accounted for nearly half of the biomass in North America and Europe. An installment of a longer video series introduces these strange plants and describes their features, adaptations, and eventual demise. It...

Earth appears blue and green now, but an interesting video covers a theory about when our planet was purple. We know the sun emits mostly green light, so why do most plants repel green light rather than absorbing it? Did purple microbes...

Is there an attraction between every object or only between really large objects? The video, produced by Veritasium, answers that question scientifically, philosophically, and mathematically. Using a lecture format, the host discusses...

Finally, a lesson to brighten up the place! The 40th installment of the Crash Course physics series explores the physics of a light source. The narrator examines patterns between light and films and studies the oscillation patterns of...

Light can be a mysterious phenomenon. Take away some of the mystery with an intriguing video lesson. The 38th lesson of the Crash Course physics series studies the movement of light waves. Topics include refraction and reflection as well...

Electricity has an interesting history. Consider the development of electric current into usable forms while viewing the 37th lesson in a Crash Course video series on physics. Using Maxwell's Equations, the instructor addresses...

Temperature can be hard on outdoor structures. Learn how engineers consider thermal energy effects while constructing structures such as bridges. The video lesson also considers how heat affects gases by exploring the ideal gas laws....

Help your classes visualize light as a wave using an engaging video lesson. The 39th lesson of the Crash Course physics series highlights the characteristics of a light wave. The lesson continues by analyzing the behavior of waves...

Take an in-depth tour of the world of AC circuits. Crash Course continues with its 36th lesson by describing the current and voltage of AC circuits. The instructor also includes a discussion of inductors, capacitors, and resistors...

Give credit where credit is due—thank Ampere any time you use an electric motor! The 33rd installment in the Crash Course physics series explains how Ampere's Law applies to a long, straight wire. The discussion then expands to the...

Your classes are sure to be attracted to the 32nd lesson in the exciting Crash Course physics series. Scholars learn the basics of magnetism and the forces created from current running through a wire. The lesson includes an application...

Explore the basics of electric current with an introductory video lesson. The 28th installment in the Crash Course physics series discusses characteristics of electric current. An explanation of Ohm's Law helps scholars understand the...

Help your classes realize their potential! A thorough lesson on potential electric energy helps scholars understand the basics of voltage and capacitors. The instructor also shows how to calculate electric potential energy in the 27th...

Help your classes visualize the invisible. The 26th episode in a Crash Course physics playlist highlights the fields created by charged particles. Using examples and diagrams, the presentation demonstrates the magnitude and direction of...

Your classes are sure to get a charge out of this lesson! A video lesson explores positive and negative electric charges related to static electricity. The instructor then moves on to a discussion of charged particles in an atom. This is...