An evaluation of object oriented example programs in introductory programming textbooks

Research shows that examples play an important role for cognitive skill acquisition. Students as well as teachers rank examples as important resources for learning to program. Therefore examples must be consistent with the principles and rules of the topics we are teaching. However, educators often struggle to find or develop objectoriented example programs of high quality. Common examples are often perceived as not fully faithful to all principles and guidelines of the object-oriented paradigm, or as not following general pedagogical principles and practices. Unless students are able to engage with good examples, they will not be able to tell desirable from undesirable properties in their own and others' programs. In this paper we report on a study in which experienced educators reviewed a wide range of object-oriented examples for novices from popular textbooks. This review was accomplished using an on-line checklist that elicited responses on 10 quality factors. Results show that the evaluation instrument provides a sufficiently consistent set of responses to distinguish examples. The paper then goes on to examine some of the characteristics of good and bad examples and how this study will influence the evolution of the evaluating instrument.