The HP-28S, Calculus, and Programming

John Selden, Annie Selden, Michael Morrison, Randy Weems and Shawn Yeager. Proceedings of the 2nd Annual Ohio State University Conference on Technology in Collegiate Mathematics, Addison-Wesley (1990), pp. 283–286.

The first two authors report on a yearlong experimental calculus course taught with the HP-28S, which led to a third-quarter course in algorithm design. The last three authors were the freshmen who took it, and the programs printed in the paper are ours.

John Selden taught the calculus course at Tennessee Tech. It was run without a textbook and without worked examples — students got the definitions and theorems, solved the problems at home, and presented and defended their own solutions at the board, with calculators allowed and encouraged on every test and exam. When some of us kept programming in our own time, he built a third course around it, ran it like a research seminar, and then put the student work in the proceedings. The paper observes that “it is unusual for undergraduates to have enough knowledge for such opportunities to arise, especially in mathematics.”

The programs it prints are a scrolling library, a drawing tool, and a game. Two of those survive here with their stories: DOODL, which drew the artwork, and Space Chase, which you can still play. For the game, this paper is the only place the source was ever formally archived — the HP-28S had no way to save a program to anything, so a conference proceedings in a university library outlasted every disk in the house.

This is the earliest published work in the catalog, by six years.