This study presents a case of a problem that did not originate in theory but rather ended in theory. It addresses the issue of the prevalent, traditional public view of the nature of mathematics and that of its teaching and learning that might hamper mathematics reform. In this study, we present a five-day professional development programme that was designed and conducted within the context of practice-oriented research to help elementary school principals to enrich their views of mathematics in order to see mathematics in a different way, more aligned with mathematics reform. Data was generated before, during, and at the end of this programme, and results showed significant enrichment in participants' views of mathematics. By using the Variation Theory of Learning, this study aimed to understand how this programme of short duration can make a difference. The core tenet of Variation Theory is that people learn through experiencing differences and similarities (in this order). The Variation Theory of Learning is used as a lens to see the programme's framework, its activities, and outcomes. The analysis clarified that principals' ways of seeing mathematics were enriched when they experienced patterns of variations and invariance, in particular, the pattern of contrast.