Here are a few comic strips dealing with extrapolation.  Each is accompanied by a question I would ask students about the strip.

1) Explain this comic strip using knowledge from the course.

(This strip is by Randall Munroe and can be accessed at http://xkcd.com/605/)

2) Read this comic strip by Randal Munroe and answer the following questions.

(This strip can be accessed at http://xkcd.com/1007/)

a) For which span of years does the Munroe have data on the frequency of the use of the word “sustainable”?

b) Munroe made a model of this data.  Does the model fit the data well?

c) Munroe used his model to predict the frequency of the word “sustainable” in 2061.  What percent of words does he predict will be ”sustainable” in 2061?  Is this an example of interpolation or extrapolation?  Is this prediction likely to be valid?