Objects On The First Day

A Role-Play Exercise


Suppose you want to teach object-orientation, starting from the first day of the first course. Yes, you can do it.

Steven K. Andrianoff and David B. Levine of the Computer Science Department at St. Bonaventure University presented a paper at SIGCSE 2002 that shows one technique for doing this.

The following Powerpoint slides should be printed 4-up and separated into individual cards. One card is given to each of eight students. After a few minutes of familiarity, the instructor sends messages to individual students, by name. It may be helpful if the students wear name tags if you do this before you learn their names.

Emphasize that all are Acrobats and all have the same protocol. I put the Java verison (an interface) on the board before I start. This is the first Java they have seen, of course.

Role Play Presentation Cards (These cards, in Powerpoint, are by Bergin, based on the above noted paper.)
Role Play Presentation Cards (This version is in Adobe Acrobat)

Send messages to the students, like:

Mary clap 3

John twirl 2


After the exercise, the instructor should point out what has been seen. The list includes

Moreover, it emphasizes a fruitful metaphor for learning objects: Objects are something like people.

Later in the course, if you use CRC cards for design, the CRC cards themselves can be used to role play the behavior of a system.

You can also refer back to the "game" when you cover the above topics in detail later.

Note that multiple identical cards is intended. Classes get instantiated multiple times.


Once you've done this you can go to the next step. See The Object Game.

If you improve and adapt these cards, I'd love to see the results.

Last Updated: May 6, 2002