Rivers are one of nature's most powerful forces -- they bulldoze mountains and carve up the earth, and their courses are constantly moving. Understanding how they form and how they'll change is important for those that call their banks...

Paul Andersen gives ten tips on increasing comprehension.

In this video Paul Andersen defines and explains the importance of the mole. The mole is simply a number (like a dozen) used to express the massive number of atoms in matter. It serves as a bridge between the mass of a compound and the...

Origami is helping to ease our journeys back from space, and astronomers are learning more about coronal mass ejections from a distant star!

In this video Paul Andersen explains how energy flows in ecosystems. Energy enters via producers through photosynthesis or chemosynthesis. Producers and consumers release the energy from food through cellular respiration. An...

Australians call them “runners." The British know them as “trainers.” Americans refer to them as “sneakers.” Whatever you call them, these casual shoes are worn by billions of people around the world. Today, roughly 23 billion shoes are...

In this video Paul Andersen explains how matter moves from the environment into living organisms and back into the environment. Food webs are used to show how matter and energy move through organisms. Ecological pyramids show that...

The planets in our solar system have a very specific order. But have you wondered why they have the order they do?

In this video Paul Andersen explains how the resistivity of a material opposes the flow of charge. Conductors (like metal) will have a low resistivity and insulators will have a high resistivity. Semiconductors will have a moderate...

How do magnets work? Why do they attract and repel at long distances? Is it magic? No... it's quantum mechanics, and a bit more, as we explain in this, the longest MinutePhysics video ever.

Paul Andersen takes you on a tour of the cell. He starts by explaining the difference between prokaryotic and eukaryotic cells. He also explains why cells are small but not infinitely small. He also explains how the organelles work...

Today on Crash Course Astronomy, Phil explains comets. Comets are chunks of ice and rock that orbit the Sun. When they get near the Sun the ice turns into gas, forming the long tail, and also releases dust that forms a different tail....

New ReviewIt just keeps going!

New ReviewSpace is full of mysteries — from Odd Radio Circles that may be supernova remnants or even wormhole throats, to Jupiter’s fleeting blue sprites and elves flashing above storms.

New ReviewAprende cómo mejorar los hábitos de estudio, para qué sirve el ciclo de estudio y algunos métodos de aprendizaje o técnicas para aprender de manera fácil. Conoce los 5 pasos del ciclo de estudio que te ayudarán a mejorar tus hábitos de...

In this video students will make observations to identify materials based on their properties. Students will set up their own experiment in which they will identify the properties of ten types of matter. The video correlates to the Next...

This video explores the fascinating processes of heating and cooling. Vivid, real-world examples help students understand the difference between changes that can be reversed and those that cannot be reversed. In the activity students...

Spangler has the cure!

In this video, we present a structured study plan designed to guide your preparation for the CCNA certification exam.

A neutron star spinning at 1 revolution per second is on the edge of tearing itself apart. This lesson breaks down the physics of rotational stability, showing how gravity and circular motion determine the star's minimum mass.

This educational video provides a clear and concise overview of the key concepts of copyright, public domain, and fair use, and how they impact creators in the United States. Through easy-to-understand language, viewers learn about the...

At 5:30AM, dawn on July 16, 1945 near a small town called Alamagordo New Mexico, the course of human history was changed. The first atomic bomb was detonated that day, and sealed the fate of humanity....

Learn how to calculate the gravitational force between a hollowed-out sphere and a point mass using mass subtraction and superposition—an essential technique for solving complex gravitation problems in AP and IB Physics.

Howcast - A state-of-the art blend of padding and material, cycling shorts are designed to cushion and contain. Selecting the right fit and style for your body and ride technique is critical to enjoying the sport.