Conventional programming paradigms have limitations where support for constructionist learning is concerned. This paper illustrates the merits of an alternative approach to giving support for constructionist learning, based on the principles of Empirical Modelling (EM), with reference to an algorithm from database theory. Effective model-building for constructionist learning has to support activities relating to three roles: that of student, teacher and developer. This paper aims to show that EM brings far greater conceptual unity to interactions in these roles than is typically found in conventional approaches to educational software development.