First Day of Class

It’s the start of a new semester at most colleges and universities, so I thought it would be interesting to hear how instructors use clickers on the first day of class.  I’ll share what I did on the first day last week, and I’ll invite you to share your creative first-day uses of clickers in the comments below.

I’m teaching an undergraduate linear algebra course this spring.  For an application-oriented course like this one, I like to spend the first day of class showing students examples of the kinds of problems they’ll be able to solve by the end of the semester.  I find that this helps students see value in studying the subject at hand.

One of the problems we looked at last week dealt with modeling a population of spotted owls.  (I adapted this problem from David Lay’s linear algebra textbook.)  The population consists of juveniles (owls less than one year old), sub-adults (owls between one and two years old), and adults (owls at least two years old).  Each year some proportion of adults produce juveniles as offspring, some proportion of juveniles survive to become sub-adults, some proportion of sub-adults survive to adulthood, and some proportion of adults survive to live another year.  The relative sizes of the proportions I just mentioned determine what happens to the overall population level over time.

I had my students consider various birth and survival rates and respond to the clicker question, “Given these rates, in the long run does the population increase, decrease, or level off?”  In the first scenario, it was clear to most students after a few minutes of small-group discussion that the high birth and survival rates meant that the population was likely to increase over time.  Having figured out the first scenario, the students responded very quickly to the second scenario, one in which low birth and survival rates meant that the population decreased over time.

Then I presented a third scenario, one in which it was not so clear what would happen to the population given a particular set of birth and survival rates.  Although one student quipped that the answer must be “level off” since that was the only answer choice we hadn’t used, most students acknowledged that it wasn’t obvious from the given rates what would happen to the population in the long term.  This allowed me to make the point that we’ll have to develop some mathematical modeling tools in order to analyze this situation accurately and make valid predictions.  This, I hope, provides students with some motivation to learn about those tools later in the semester.

So what kind of clicker questions do you ask on the first day or in the first couple of weeks of class to get your students off to a good start?