Geometry

Quadrilaterals... explore those 4-sided figures.
Can you identify the quadrilaterals?
Sorting Quadrilaterals
The Bottom Line on Quadrilaterals with a Game
Shape Tool

Angles
Turtle Pond
Circle Tool
Cyberchase Star Gazing
Using a Protractor
 
Area and Perimeter
Perimeter
Everything You Wanted To Know About Perimeter and Area!
Area of Squares and Rectangles
Area of Complex Figures 
Compare the Area and Perimeter of Two Figures
Shape Surveyor:  You never know what you'll find if you dig geometry.
Math Playground's Area and Perimeter of Rectangles
How does changing the length or width of a rectangle affect it's area?
Building a Putting Green

Using Geometry Vocabulary
Similar and Congruent
Congruent, Similar, or Neither
Lines of Symmetry
Lines, Line Segments, and Rays
Parallel, Perpendicular & Intersecting Lines

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