This instructional activity introduces students to the important concept of density. The focus is on the more easily understood densities of solids, but students can also explore the densities of liquids and gases. Students devise...

Practice decomposing irregular shapes to find their area. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints. CCSS.Math.Content.3.MD.C.7.d Recognize area as additive.

At the end of this lesson plan about formulas, young scholars will be able to identify and apply the correct formula for a given situation, solve for any unknown component of the formulas for perimeter, circumference, and area of regular...

Investigate some of the mathematical challenges Boston engineers had to deal with during the Central Artery Tunnel Project (the "Big Dig"). This video focuses on the irregular shape of the casting basin and the volume calculations...

This site helps you understand how the 206 bones that compose the adult skeleton are divided into five categories based on their shapes.

This commercial site gives general information on pearls, including their physical properties and where they are found.

Create regular and irregular polygons and determine the angles and side lengths with this interactive exercise. Use Safari or Chrome browser.

This website has basic definitions for most polygons, regular and irregular.

This lesson explains how to break composite figures into more simple shapes in order to find its area. It is 2 of 4 in the series titled "Finding the Area of Composite Figures."

Explains what galaxies are and their different shapes. Includes details on the Milky Way.

A simple lab experiment for students to find the density of two solids and a liquid (does not use water displacement). Note that number 1d should not state "weighs" since mass is being found.

Explore this awesome tool that animates a robot that contains sliding arms (like those used in hydraulics) and rotating arms like those used in rotary motors. The exploration asks students to consider how to find the area drawn by the...

If you sit under a leafy tree on a sunny day, you may notice spots of sunlight on the ground from light passing through spaces between the leaves. Try putting a piece of cardboard on the ground and examining the spots of light on the...

Explore the world of prisms in this mini-lesson by learning what are prisms, definitions with shapes and examples, the difference between regular, irregular, right, and oblique prisms, the surface area of a prism, and the volume of a...

This site from the Illinois Institute of Technology provides a lab activity in which students determine the location of the center of mass of an irregularly shaped object. Observations are related to the balancing point of the object....

Drawings and discussion of several methods to estimate the area of an irregular shape, like the state of Texas.

Drawings and discussion of several methods to estimate the area of an irregular shape, like the state of Texas.

Drawings and discussion of several methods to estimate the area of an irregular shape, like the state of Texas.

Drawings and discussion of several methods to estimate the area of an irregular shape, like the state of Texas.

A map from 1911 of a portion of the Laurentian Plateau region of North America showing the drainage and lake network west of Lake Nipigon. The map shows the division line for waters flowing to the Albany and the Winnipeg river systems,...

An irregularly shaped terra-cotta seal contains a fish design. The details are not clear, probably because it has become worn due to the frequency of its use in everyday life.

The irregularly shaped piece of stone is an educational model used to train individuals in the art of depicting human figures. It has a figure of a man on both sides.

Introduces the concept of polyhedrons by learning the definition, types, and where they are found. Check-out the solved examples for better understanding and try your hand at solving a few interactive questions at the end of the page.

In this video segment from Cyberchase, Harry uses tessellations to wallpaper his apartment.