The protractor was invented several thousand years before a more complex version was developed in the 1800s. Find out who invented the protractor with tips from Steve Jones, who uses a white board to aide in his presentation.

Euclid of Alexandria revolutionized the way that mathematics is written, presented or thought about, and introduced the concept of mathematical proofs. Discover what it takes to move from a loose theory or idea to a universally convincing proof. (04...:38)[more]

The ruler was invented in the 16th century by William Bedwell, and it is used for drawing straight lines and taking measurements. Use a ruler for math, science, and artistic purposes. (00:59)

The protractor was invented in 1801 by Joseph Huddard, and this device is used to measure angles from zero to 180 degrees.
Expert: Samir Malik. Samir Malik has tutored Austin, Texas-area high school to elementary school-level students in all subjec...ts for the last three years. Filmmaker: Todd Green (01:41)[more]

This video explains how the abacus is used and what the beads mean. It goes slowly, but students would benefit from having one or a copy of one to help them follow. This might make a good tool for students who benefit from hands on learning. (5:48)

The ruler was invented by different civilizations of different time periods. Discover the origin of the ruler with tips from Steve Jones who uses a white board to aide in his presentation.
Though the video is in English, there are English captions... at the bottom of the screen which may be helpful in a large room.[more]

Learn who invented the calculator from a mathematics instructor. The math instructor explains that the calculator was invented by the Chinese in the form of an abacus. He shows and explains various devices used in history on a whiteboard.

String Theory is a theory in particle physics that attempts to describe the reality of our Universe and bring together Quantum Mechanics and General Relativity on the nature of space/time. This has some leading physicists believe that String Theory ...gives us our best shot at grasping the true physical makeup of our Universe. This is the story of how this concept has come down through time. There are more than one part, but this gives students an idea of what this concept is about.[more]

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