Within a 10-mile radius of the campus where the students are taking this class, have students put together a list of the tattoo parlors. Have them call each and find out how long they have been in business. Have them visit a few of the parlors that have been around the longest and interview the owner as to how many shops there were 10 years ago. Have the students then construct a list of the tattoo shops at that point in time. Students should draw conclusions based on this comparison.