In this video Paul Andersen describes the new AP Biology Exam. This exam will be given for the first time in May of 2013 and will be different from all previous exams. In this video Paul Andersen describes the scoring and the two parts...

An animated introduction to the Fourier Transform, winding graphs around circles.

We've been trying to count the galaxies in the universe since the mid '90s, but our estimates change as our tools improve. So what does our current estimate really mean?

Join The Amoeba Sisters as they explain the biotechnology PCR. This video goes into the basics of how PCR works as well as two examples of its potential use. Table of Contents: 00:00 Intro 1:34 How does PCR work? 4:31 Why use PCR? 5:10...

Paul Andersen explains how signal transduction pathways are used by cells to convert chemical messages to cellular action. Epinephrine is used as a sample messenger to trigger the release of glucose from cells in the liver. The...

You’re on the trail of a werewolf that’s been terrorizing your town. After months of detective work, you’ve narrowed your suspects to one of five people. You’ve invited them to dinner with a simple plan: to slip a square of a rare...

Paul Andersen describes the four major biological molecules found in living things. He begins with a brief discussion of polymerization. Dehydration synthesis is used to connect monomers into polymers and hydrolysis breaks them down...

Two minute video for middle school on the causes of climate change

Howcast - Learn to make a princess castle cake for a kids birthday party from Essential Cakes' Etwin Gordon in this Howcast video, part 10 of an 11-part series.

Howcast - Learn how to make a ladybug cake for a kids' birthday party from Essential Cakes' Etwin Gordon in this Howcast video, part 5 of a 7-part series.

Howcast - Learn how to play the nine-stroke roll from drum teacher Jason Gianni in this Howcast drum video.

Howcast - Learn how to play a hi-hat from drum teacher Jason Gianni in this Howcast drum video.

Howcast - Learn how to exercise portion control from nutrition expert Alex Jamieson in this Howcast video.

Howcast - Learn how to identify and handle an infant rash from parenting coach Tammy Gold in this Howcast baby care video.

Howcast - Taking tax deductions on business expenses is one of the advantages of being self-employed. As a savvy business owner, you need to know which purchases qualify and which don't.

Howcast - Learn the best muscles to foam roll if you are a runner in this Howcast video featuring certified NYC trainer Amanda Edell.

Howcast - Philadelphians are passionate about their city's sandwich, but you can learn to make a world-class cheesesteak no matter where you live.

Howcast -No calculator handy? Here's how to divide numbers the old-fashioned way.

Howcast -Find out if insurance will cover your nose job if you have breathing problems in this Howcast video featuring plastic surgeon Robert J. Morin, M.D..

Howcast -Learn how to store, freeze and reheat homemade baby food from Petit Organics founder Michelle Muller-Marinis in this Howcast video.

Howcast -Learn how to make kiwi puree baby food from Petit Organics founder Michelle Muller-Marinis in this Howcast video.

Howcast - Pick up four parallel parking tips and tricks in this Howcast video with A-Club Driving School.

Howcast - Learn how to make a no-sew tutu from ribbon and tulle with designer Jennifer Wiese in this Howcast video, part 2 of a 3-part series.

Howcast - Learn how to make an old t-shirt into a no-sew tote bag with designer Jennifer Wiese in this Howcast video, part 3 of a 4-part series.