@internet4classr I4C

## Understand that if a scale factor describes how corresponding lengths in two similar objects are related, then the square of the scale factor describes how corresponding areas are related, and the cube of the scale factor describes how corresponding volumes are related. 0706.4.3

1. Applications of Culture in Mathematics - Students will use the concepts of similarity,scale factors, and conversion factors to make scale drawings of different Malawian houses
2. Designing a Soccer Field - lesson plan using scale drawings [This expired link is available through the Wayback Machine Internet Archive. If the page doesn't load quickly click on Impatient? at the bottom right of the page.]
3. Designing a Tennis Court - lesson plan using scale drawings [This expired link is available through the Wayback Machine Internet Archive. If the page doesn't load quickly click on Impatient? at the bottom right of the page.]
4. Drawing Scale in CAD - summarizes the relationship between drawing scale and drawing scale factor and describes how to work with them in new and existing drawings [This expired link is available through the Wayback Machine Internet Archive. If the page doesn't load quickly click on Impatient? at the bottom right of the page.]
5. Dilation - the description of a dilation includes the scale factor and the center of the dilation
6. Dilation - definition with a good drawing to illustrate dilation from Wolfram MathWorld
7. Dilation of a Polygon - adjust the slider to change the scale factor
8. How to Perform Dilations - Math Warehouse provides three clickable animations explaining dilation
9. Intuitive Notion of Dilation - definition and several good illustrations to explain the concept of dilation
10. Linking Length, Perimeter, Area, and Volume - NCTM lesson plan comparing the perimeter and area ratios of similar rectangles with various scale factors
11. Pictures to use in scale factor activities - Yankee Stadium - Orange Bowl Stadium
12. Playing with Dilations - an interactive applet from the National Library of Virtual Manipulatives
13. Scale Drawing Problems - a worksheet to print with ten practice problems
14. Scale Drawings and Models - seven practice problems on a worksheet
15. Scale Drawings and Scale Models - a 17 slide PowerPoint show could be used as a lesson
16. Scaling Away - Students will measure the dimensions of a common object, multiply each dimension by a scale factor, and examine a model using the multiplied dimensions.
17. Solving proportions - This lesson presents solving proportions by using cross product to find unknown terms
• Scale Drawings - After you understand proportions, try the lesson on making scale drawings
18. Understanding Scale Factors - Similar Triangles: Perimeters and Areas - When two triangles are similar, the reduced ratio of any two corresponding sides is called the scale factor of the similar triangles

Internet4classrooms is a collaborative effort by Susan Brooks and Bill Byles.