4.1 Introduction

Every freshly made course or lesson is unique. It carries the fingerprint of its designer’s design decision-making. The last convolutions in the print come from decisions made as you test-and-revise (activity 4.3) a thought-up, worked-out design. The test is made with the help of a small group of learners, chosen at random but representative of the student population for whom the course or lesson was designed. 

In the programme writing practice that I knew in New York in the ’60s and ’70s, it was the custom to use eight learners in a try-out. Such a ‘jury of eight’ were able to pick up most of the design mistakes that had been made in preparing self-study programmed learning systems. The eight usually represented a heterogeneous population of several hundred users. Habit, and previous good results, would make me choose eight for testing the design of a new course or lesson today. Practicality might, of course, make one settle for a smaller group of three or four or even two.