The Pauling Scale is used to understand bonding due to electronegativity. Bond types are classified. [11:39]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

So we know that all matter is made up of atoms, but what is an atom made out of? Chemists describe the structure of atoms using models. This section will cover the Bohr model, photoelectric effect, absorption and emission spectra, quantum numbers, and electron configurations.

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

In this animation produced by WGBH and Digizyme, Inc., see how molecules of DNA are separated using gel electrophoresis, and how this process enables scientists to compare the molecular variations of two or more DNA samples.

A video lecture that discusses how elements relate to atoms. Also discussed are protons, electrons, and neutrons. [13:08]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Video tutorial explores how elements relate to atoms and provides the basics of how protons, electrons, and neutrons make up an atom. [13:08]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

A demonstration involving an elephant and a feather and explanation of why all objects maintain the same acceleration in the state of free fall without any air resistance.

Create a giant foaming reaction and wow your friends with the classic science demonstration! With just a few simple ingredients, you can make something that looks like toothpaste being squeezed from a tube -- but so big, it must be for elephants!

Canadian Wildlife site features the North American Elk. Highlights its habitats and habits, range, feeding and breeding characteristics.

Young children are not likely to think past their piggy banks when it comes to safe places to set money aside for those special items. In this short module, your students will learn that a bank account offers security and a return on their savings. This content from Econ Lowdown also features alignment to national Financial Literacy and/or Economics standards.

This lesson focuses on the ellipsis. The following topics are discussed: how it is written, its purpose, its uses, how to punctuate sentences with ellipsis, and examples of sentences with ellipses. Text and audio formats are used.

This video lesson focuses on the proper use of the ellipsis, including how to type them correctly and how to use them in various types of quotations. [8:57]

A video lesson explaining the form and function of an Em dash followed by a PowerPoint providing several examples of Em dash usage. [2:48]

In this free tutorial, learn how to use common email features and practice proper etiquette.

Lessons include: (1) Introduction to Email. Get an introduction to how email works. (2) Common Email Features. Learn common email features and functions. (3) Contacts and Calendars. Learn how to add email contacts and add dates to an email calendar. (4) Email Etiquette and Safety. Understand email etiquette and safety so your emails are as protected and professional as possible.

Sal Khan gives a video tutorial on the causes of WWI focusing on the empires and imperialism in the early 1900's. [7:36]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

This site contains an interesting account of the life of Claudius. Includes quotes from ancient and modern historians, as well as a scathing description of his second wife, Agrippina.

PBS provides a fascinating glimpse of Egypt's New Kingdom, arising "more than one thousand years after the pyramids were built." Concentrating on the lives of seven pharaohs (one of them a woman), the site includes a timeline, lesson plans (on Egyptian Daily Life, Pharaohs, and Beliefs), and information on the making of PBS's "Egypt's Golden Empire" TV series. Visually impressive, with great pictures of pharaohs, artifacts, reenactments, and more.

Learn to write your name in hieroglyphs on this PBS site that explains hieroglyphic writing and the sounds of the hieroglyphs. Click on Kamose Stela to see and read the translation of hieroglyphic text.

This article from PBS explains the role of priests in ancient Egypt as advisors to the pharaohs among other duties. Find out why the priests grew so wealthy and important in the government.

An intriguing look at the woman's role in society in the New Kingdom. This PBS article talks about the rights of women which were unusual in ancient cultures

Learn about the Renaissance period and its cultural leaders, the Medici family. Take an interactive tour of Florence and use the interactive timeline to understand the course of the Renaissance through the centuries. Uses popups.