Title  Description  Thumbnail Image  Curriculum Topics 

Why Do Rivers Meander? 
Rivers twist and turn as they make their way to the sea. Why does this happen and how can this be explained mathematically? In this module we look at the geometry of meandering rivers. In the process we'll discover some fascinating numerical relationships. Students will learn some basic concepts about the geophysics of how rivers form, but they will focus their analysis on what is called the sinuousity ratio. This is the ratio of the straightline distance of the river and its meandering distance. This ratio reveals important characteristics of the river. Then, students will develop and examine geometric models involving circular arcs and segments to get a better understanding of the ratio. These models will first involve using a compass and straight edge to model a river. This is followed by an algebraic analysis. This module is an excellent way of tying real world concepts to geometry and algebra. The realworld application is easy to understand and yet it reveals a wealth of math concepts to be explored. 

Halloween Math Activities 
Turn the Halloween season into an opportunity to do some math activities! In this module, you'll find a clever collection of arithmetic, algebra, and geometry activities.


Interactive Crossword PuzzleCircles 
This interactive crossword puzzle tests knowledge of key terms on the topic of circles. Note: The download is a PDF version of this puzzle. 
Definition of a Circle  
Math Example: Circular Area and Circumference: Example 01 
Circular Area and Circumference: Example 1. Finding the area of a circle, given the radius as a number. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 02 
Circular Area and Circumference: Example 2. Finding the circumference of a circle, given the radius as a number. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 03 
Circular Area and Circumference: Example 3. Finding the area of a circle, given the radius as a variable. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 04 
Circular Area and Circumference: Example 4. Finding the circumference of a circle, given the radius as a variable. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 05 
Circular Area and Circumference: Example 5. Finding the area of a circular region, given the values of the radii as numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 06 
Circular Area and Circumference: Example 6. Finding the area of a circular region, given the values of the radii as numbers and variables. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 07 
Circular Area and Circumference: Example 7. Finding the area of a circular region, given the values of the radii as variables. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 08 
Circular Area and Circumference: Example 8. Finding the area of a sector, given the values of the radius and central angle as numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 09 
Circular Area and Circumference: Example 9. Finding the arc length of a circle, given the values of the radius and central angle as numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 10 
Circular Area and Circumference: Example 10. Finding the area of a sector, given the values of the radius and central angle as variables. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 11 
Circular Area and Circumference: Example 11. Finding the arc length of a circle, given the values of the radius and central angle as variables. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 12 
Circular Area and Circumference: Example 12. Finding the area of a sector, given the values of the radius and central angle as variables and numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 13 
Circular Area and Circumference: Example 13. Finding the arc length of a circle, given the values of the radius and central angle as variables and numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 14 
Circular Area and Circumference: Example 14. Finding the area of a sector, given the values of the radius and central angle as variables and numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 15 
Circular Area and Circumference: Example 15. Finding the arc length of a circle, given the values of the radius and central angle as variables and numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 16 
Circular Area and Circumference: Example 16. Finding the area of a circular region, given the values of the radii and central angle as numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 17 
Circular Area and Circumference: Example 17. Finding the perimeter of a circular region, given the values of the radii and central angle as numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 18 
Circular Area and Circumference: Example 18. Finding the area of a circular region, given the values of the radii and central angle as variables. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 19 
Circular Area and Circumference: Example 19. Finding the perimeter of a circular region, given the values of the radii and central angle as variables. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 20 
Circular Area and Circumference: Example 20. Finding the area of a circular region, given the values of the radii and central angle as variables and numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 21 
Circular Area and Circumference: Example 21. Finding the perimeter of a circular region, given the values of the radii and central angle as variables and numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference  
Math Example: Circular Area and Circumference: Example 22 
Circular Area and Circumference: Example 22. Finding the area of a circular region, given the values of the radii and central angle as variables and numbers. Note: The download is a JPG file. Related ResourcesTo see the complete collection of Math Examples on this topic, click on this link: https://bit.ly/3bLNAVu 
Area and Circumference 