In this video Paul Andersen shows how carbon dioxide in the atmosphere is causing a decrease in the pH of the oceans. The carbon dioxide combines with the water to create carbonic acid which dissociates into bicarbonate and carbonate...

In this video Paul Andersen explains how the change in angular momentum is equal to the torque applied over a given time. A sample problem and inquiry activity are included.

Squeaks and Mister Brown do some experiments with soil, and learn all about why different soils feel different!



Disciplinary C

ore Ideas:

PS1.A: Structure and Properties of Matter - Matter can be described...

In this video Paul Andersen explains how water quality can be degraded by pollutants. Wastewater is the main source of water pollution and can be measure using the BOD (biochemical oxygen demand). Dead zones, cultural eutrophication,...

We've compiled our videos about sugar and sweetness here. Enjoy the rush!

In this video Paul Andersen describes both weather and climate. Weather is the day-to-day conditions on the Earth's surface, including temperature, wind, humidity, air pressure, and precipitation. Climate are the long term conditions...

You’d think that animals that lived in water wouldn’t have to drink it -- but some fish do. Learn all about how different kinds of fish get the fresh water that they need to survive.

Paul Andersen explains pH as the power of hydrogen. He explains how increases in the hydronium ion (or hydrogen ion) concentration can lower the pH and create acids. He also explains how the reverse is true. An analysis of a strong...

Have you ever noticed how easy it is to get distracted while studying - even when you know you really don't have time for Facebook, Snapchat, Cookie Clicker, or whatever else is calling you? This week we're going to help you get a better...

You're on YouTube right now, but you should probably be studying or writing that research paper. But as long as you're here, we're going to help you figure out how to get the better of your desire to procrastinate in the future. Just...

In this video Paul Andersen explains how the climate on the earth is affected by the amount of solar radiation and the greenhouse affect. The addition of anthropogenic greenhouse gases has led to global warming which is impacting humans...

In this video Paul Andersen explains how the work is a product of the external force applied to an object or system and the distance it moves. Power is a measure of the amount of work done per unit time. The work can be calculated as...

In this video Paul Andersen explains how water is unequally distributed around the globe through the hydrologic cycles. Seawater is everywhere but is not useful without costly desalination. Freshwater is divided between surface water...

In this video Paul Andersen explains how fossil fuels are formed when organic material is heating and squeezed in an anaerobic environment. Formation, extraction, advantages, and disadvantages are discussed for coal, petroleum and...

Is there a way to detect diseases like cancer and Alzheimer's before they advance too far? Doctors are using injected radioactive drugs that circulate through the body and act as a beacon for PET scanners. These diagnostic tools can...

Paul Andersen shows you how to graph data by hand. He explains the required elements of a scatter plot with a best fit line. He shows you how to properly scale and label the axes.

Why do some regions experience full-time heat while others are reckoning with frigid temperatures and snow? And why are the seasons reversed in the two hemispheres? Rebecca Kaplan explains how the shape of the Earth's orbit around the...

In this video Paul Andersen explains how engineers optimize the design solution. After a number of solutions have been identified engineers will test each of them against a given set of criteria. They will trade-off different...

Mr. Andersen explains the difference between potential and kinetic gravitational energy. He also uses physics to calculate the energy in various objects.

Today's Crash Course Chemistry takes a historical perspective on the creation of the science, which didn't really exist until a super-smart, super-wealthy Frenchman put the puzzle pieces together - Hank tells the story of how we...

Earth had a climate long before we showed up and started noticing it and it's influenced by a whole series of cycles that have been churning along for hundreds of millions of years. In most cases those cycles will continue long after...

What happens to a single ecosystem when the amount of freshwater available in it changes? Not really much good. In this episode of Crash Course Kids, Sabrina talks about ecosystems and how one small change can lead to a cascade effect in...

In this video Paul Andersen explains how objects in contact with varying temperatures will eventually reach thermal equilibrium with equal temperatures. The amount of thermal energy transferred is related to the mass and temperature of...

Water is essentially everywhere in our world, and the average human is composed of between 55 and 60% water. So what role does water play in our bodies, and how much do we actually need to drink to stay healthy? Mia Nacamulli details the...