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Wolfram Research

Wolfram Math World: Geometry

For Students 9th - 10th
This MathWorld tutorial provides detailed overviews of the concepts and theorems associated with geometry. Most of the Math World sites are extensive and some require higher math knowledge to understand, links to terms and topics are...
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National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Constructing the Orthocenter

For Students 9th - 10th Standards
Dr. Math shows how to construct the orthocenter of any triangle using a compass and straight edge.
Website
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Constructing an Ellipse

For Students 9th - 10th
Dr. Math, in a reply to a student question, mentions how you can construct an ellipse using string and thumbtacks.
Website
National Council of Teachers of Mathematics

The Math Forum: Ask Dr. Math: Building Two Column Proofs

For Students 9th - 10th Standards
Use this site to find details of how to construct a two column proof. Dr. Math responds to a question posed by a student and details the reasons for the order of steps and shows two different ways to do the same proof.
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PBS

Pbs: American Experience: Golden Gate Bridge

For Students 9th - 10th
The perfect site on the Golden Gate Bridge! PBS provides bridge math, great pictures of before, during, and after the construction of the bridge, and a special section called "Balancing Forces," that demonstrates how the "tension" of the...
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PBS

Pbs Learning Media: An Egyptian Clock

For Students 3rd - 6th
The CyberSquad must construct a clock of sorts in order to keep track of the amount of time they have to rescue Dr. Marbles in this video segment from Cyberchase.
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PBS

Pbs Learning Media: Using a Coordinate Grid

For Students 5th - 7th Standards
In this Cyberchase video segment, the CyberSquad must locate each other using a map's grid to construct a coordinate system using letters and numbers.
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PBS

Pbs Learning Media: Cyberchase: Catching the Kidnapper

For Students 3rd - 8th
In this video segment from Cyberchase, the CyberSquad and Digit construct a physical profile of the person who kidnapped Choocroca, a giant cybercrocodile. [2:49]
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NASA

Ancient Observatories: Timeless Knowledge

For Teachers 9th - 10th
This cross-curricular lesson involves geography, history, science and math, as well as 21st century literacies in technology, collaborative work and research. Students construct a sun-dial, then document their work and its results via...
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University of Maryland

The Impact of the Internet on Society

For Students 9th - 10th
Describes how information technology and the Internet are rapidly transforming the character of life and work. Changes in the fields of education, health care and business are considered. There is another link to the economic impact of...