Texas Instruments
Texas Instruments: Cross Fencing Pastures
In this activity, students use the Geoboard to determine the areas of polygons by dissecting them into parts that are squares, rectangles, and triangles.
Shodor Education Foundation
Shodor Interactivate: Factorize 2
The resource consists of student notes, instructor notes, and an interactive activity. The activity allows learners to find the factors of a given number and then draw the product as the area of a rectangle on a grid.
Shodor Education Foundation
Shodor Interactivate: Factorize
This Shodor site gives a brief explanation of factorization, and it allows you "to find all of the factorizations of a given number and then draw the product as the area of a rectangle on a grid."
Shodor Education Foundation
Shodor Interactivate: Perimeter Explorer
Use this applet to find the perimeter of a variety of shapes with the same or different areas.
Math Open Reference
Math Open Reference: Quadrilaterals
A complete reference guide to quadrilaterals including squares, rectangles, parallelograms, trapezoids, and rhombus. It provides definitions and interactive activities that enhance further explanation.