Students understand that a tessellation is covering of a plane with a pattern of figures so there are no overlaps or gaps. They draw quadrilaterals and triangles and explore monohedral, dihedral, and trihedral tessellating patterns.

This site contains a wealth of problems that deal with the basic definitions of medians, altitudes, angle bisectors, and perpendicular bisectors or the defining characteristics of the different types of triangles. There are also...

This site provides definitions of different types of polygons and figures.

Here is a huge collection of teacher resources for teaching 2-D and 3-D shapes. Includes smartboard and PowerPoint presentations, as well as worksheets and helpful hints.

Did you know that two-dimensional shapes are also called polygons? This lesson describes the various 2-D shapes and includes two interactive games to reinforce skills.

Guide a mummy safely through the burial chambers of a pyramid as you solve length and area problems in basic to advanced geometry. There are four game zones that deal with circles and triangles, quadrilaterals, the Pythagorean Theorem,...

Find the area and perimeter of triangles and quadrilaterals by first using the Pythagorean Theorem to find missing side lengths. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or...

Investigate the properties of triangles, quadrilaterals, and regular polygons using this interactive Learn Alberta math resource. Students are able to practice classifying shapes based on their different properties. Be sure to follow the...

This activity is designed as an introduction to using the Carbri Jr. application on the TI-83+/84+ calculators. Students are guided through the menu system and are shown how to draw triangles, quadrilaterals and and a pentagon. Perimeter...

Explains the basic concept of a rectangle with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

The interactive Cabri Jr. geometry application makes it easy to measure the area of triangles and quadrilaterals. In this activity, students will explore some interesting area relationships in quadrilaterals.

Explains the basic concept of a square with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

[Free Registration/Login Required] This flipchart reviews segments, parallel and perpendicular lines and then introduces polygons including quadrilaterals. It has many real world examples of shapes and includes Activote assessment.

A comprehensive tutorial from AAA Math that contains explanations, interactive practices and challenging games.

In Spanish. Interactive activities online on various geometric and trigonometric concepts such as area, perimeter, secants, tangents, etc. A terrific resource for students. Site is organized acoording to shape. (triangle, quadrilaterals,...

This site provides a detailed overview of Heron's Formula. Content includes a definition, example, and formula.

[Free Registration/Login Required] This flipchart provides students with notes and practice with using formulas for finding the area of triangles and quadrilaterals.

Learn what an interior angle of a polygon is and how you can calculate their value in triangles, quadrilaterals, and pentagons. Includes a chart that overviews the "general rule" for determining the sum of internal angles in any polygon...

Learn about the properties of 2-D shapes: circles, triangles, polygons, and quadrilaterals. Includes information, video, and examples about each, with games and quizzes for reinforcement.

You can pick up some valuable pointers on how to find the area of a triangle, rectangle, and other quadrilaterals. When you finish working your way through the pages you can take an on-line "Test Bite," and check your understanding.

In Spanish. Gain your knowledge of tessellation with this interactive activity. Topics include identifying regular and semi-regular tessellations and figures that will tessellate. [Requires Java.]

An integrated geometry lesson on spatial sense in which students identify and use different shapes to create a tessellation. "Through a variety of modalities such as writing, music, art, poetry, and literature, students are introduced to...

This SMART Notebook lesson allows students to characteristics of polygons by exploring vocabulary and sample problems.

Students may use this computer applet to explore angle sums of triangle, quadrilaterals, pentagons and hexagons.