These sites are about crop circles. Read general information about crop circles, including its history and different theories on how they are created, as well as a design aspect. Find out how to create crop circles using geometric knowledge and how to implement them on fields. Includes a photo gallery, lesson plans, and interactive reconstructions. There are also links to eThemes Resources on symmetry and circumference of geometry.

Find out about different theories of how crop circles are created, locations and different patterns of the crop circles, and how to make the crop circles. NOTE: This site includes ads.

A two-page PDF file shows how mathetical patterns are related to crop cirle. There is also a step-by-step illustration of how to reconstruct the crop circle using GeoGebra. Scroll down to a link to download a software.

Learn how to construct the basics in geometry. Choose the mathemeical basics from a menu on the right and then click on bar in the middle to see interactive step-by-step illustration. NOTE: A flash-plug-in is reqired to view this page.

These sites offer many examples of how symmetry works in a variety of shapes. Find out the difference between reflection and rotational symmetry. Includes interactive sites that let you draw symmetrical shapes and manipulate them. There is a link to an eThemes Resource on tessellations.

Learn how to calculate the circumference of a circle also known as a perimeter of a circle. Find out what radius and diameter are and how to find their values. There are links to eThemes resources on perimeter.