Fractions can be a tricky concept for students although they often use the concept of sharing in their daily lives. Notation of fractions and formal vocabulary may be some reasons for that. Students may have difficulty with learning fractions since they do not like behave normal numbers (Ardogan & Ersoy, 2003; Graeber & Triosh, 1990). The aim of this paper is to understand the students' conceptual and procedural understanding of addition and subtraction of fractions. Pirie and Kieren Model is used as a framework. This model is supported with the hands-on activities and implemented with Australian students. (C) 2010 Elsevier Ltd. All rights reserved.