Use online virtual manipulatives to develop a better understanding of area, perimeter, and circumference of various geometric shapes. Learn how to estimate those measurements, too!

1) Estimator Virtual Manipulative This activity features an applet that presents three estimating situations. Problems challenge students to estimate the number of objects on the screen or estimate the length of a curve or area of a shape.

6) Triangle Explorer Virtual Manipulative Students learn about areas of triangles and about the Cartesian coordinate system through experimenting with triangles drawn on a grid.

12) Area and Perimeter of Rectangles Virtual Manipulative Click Skip Intro, then select Lessons, and then click on Lesson 12 for an interactive lesson on area and perimeter of rectangles. Help the contractors determine the proper amount of baseboards and carpet to buy.

13) Relating Area and Perimeter Virtual Manipulative Click Skip Intro, then select Lessons, and then click on Lesson 13 for a lesson on the relationship between area and perimeter of rectangles. Learn how to maximize the area and minimize the perimeter. You can also minimize area and maximize perimeter.

14) Exploring Composite Figures Virtual Manipulative Click on Grade 7, then click on Area and Perimeter and go to…
Exploring Composite Figures
Create composite figures made of several geometric shapes and determine their areas. You can also view an interactive video: “Exploring Area and Perimeter” at this web site.

20) Perimeter and Area of Similar Rectangles Virtual Manipulative Learning about Length, Perimeter, Area, and Volume of Similar Objects Using Interactive Figures: Side Length and Area of Similar Figures. How does changing the size of an object (but keeping its proportions the same) affect its area?

21) Powers of Ten Before your very eyes see the perspective expand from a 1-meter view of a rose bush to an expanded vision of 10 to the 26 power and then decrease to 10 to the negative 15.