This website, although mostly for selling artwork prints by M.C. Escher, provides a good picture of Escher's famous piece lithograph, "Convex and Concave." Includes some informative text.

This lesson plan describes a demonstration with mirrors to catch the interest of students. Should be used with intermediate or middle school students.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to calculate exterior angles of regular polygons. Students examine guided notes, review guided practice, watch instructional videos...

[Free Registration/Login may be required to access all resource tools.] In this lesson students find the measure of the exterior angles of a polygon. Students examine guided notes, review guided practice, watch instructional videos and...

[Free Registration/Login may be required to access all resource tools.] What a lens is and what it does, concave and convex lenses.

An image of "Self-Portrait in a Convex Mirror", created by Parmigianino, c. 1524 (Oil on wood, diameter 24,4 cm).

A discussion from Georgia State University of different types of mirrors and the images which they create. Discusses different instruments which use mirrors to produce images.

This site from Georgia State University discusses the means by which mirrors and lenses are combined to produce an optical instrument which accomplishes a specific purpose. Good illustrations.

This calculus tutorial with curved mirrors includes narrative and video presentations as well as other interactive tools.

Included here are illustrations of reflections from a plane mirror, a concave mirror and a convex mirror.

This is a question response page from the University of Regina where you will find an algorithm for finding the number of degrees of any convex polygon.

This site provides a basic experiment that shows how a lens works. This lesson plan explains nearsightedness and farsightedness. It also explains concave and convex lenses.

This site gives the general definition of a octagon with examples of regular convex and irregular concave octagons. The site has links to related terms, everyday examples, challenging problems, more information, and the interactive check...

A simple activity to investigate how light reflects off a flat surface, a convex one, and a concave one. With a link to an article on reflection.

An experiment using Jell-O to create lenses, to see how light behaves with flat, concave, and convex lens surfaces. With an explanation of what is observed, and a link to an informative article on lenses.

This site provides an image of M.C. Escher's lithograph, "Convex and Concave," which can be enlarged by clicking on it. Included is a brief quote, "from the text of M.C. Escher - the Graphic Work," which provides some insight into...

Kids learn about lenses and light in the science of physics including concave, convex, converging, diverging, focal point, meniscus, and Plano lenses.

[Free Registration/Login Required] This flipchart defines a polygon and the classification of concave and convex polygons.

This is a question response page from the University of Regina where you will find an algorithm for finding the number of degrees of any convex polygon.

Provides a discussion of curved mirrors and ray diagrams. Shows and explains the process of drawing a ray diagram to determine the image location, size, and orientation.

This is an informative site from Georgia State University. It gives a discussion of the thin lens equation and an illustration of its use in determining the image distance based upon the object distance and the focal length.

[Free Registration/Login Required] A simulation exploring how contact lens correct your vision!.

Hotmath provides 21 practice problems dealing with systems of equations and inequalities. Each of the practice problems include a step-by-step guide for solving their algebraic problem.

This tutorial with video and slideshow components investigate the characteristics of polygons as well as how to calculate the interior and exterior angles of any polygon. It offers two PowerPoint presentations and two videos that feature...