Sunday, November 8, 2009

Rate of Change/ Finding Slope

When getting ready to introduce slope, it is fun to start out with an activity that demonstrates slope as the rate of change. The activity that I am going to share with you today is simple to do and gets the point across quite nicely. You will need beakers filled up halfway with water, centimeter cubes, graph paper and rulers. Students are introduced to an Aesop's Fable telling the story of the Raven, who during a great drought, was able to access water in a well by dropping pebbles into the well until the water rose high enough for him to reach it with his bill.
Students act out the story by dropping centimeter cubes into their beakers, and keeping track of the water level in the beaker depending on the amount of cubes dropped into it. Students can take their table of information which compares the number of cubes dropped in to the water and the water level, and graph the results on their graph paper. Students should notice a linear correlation that demonstrates rate of change. It is easy to then introduce slope (rise/run), as the rate of change following this activity. You can then tie in "real life" rate of change/slope activities such as monthly cell phone bills, etc.

1 comment:

  1. We just posted a video with Prof. Edward Burger on this exact subject! I really think the video combined with this activity would help students truly understand this concept.
    Thanks for sharing a great activity that brings rate of change into the real world!