This paper examines ten K-8 preservice teachers' visual representations of fraction operations using the four main pattern blocks. Data consist of figures made using the pattern blocks, drawn colored representations, and detailed written comments and algebraic formalism. The theoretical framework is drawn from representational theories and analyses of fraction operations, and work on coordination of different levels of units. The main result is that only those teachers meaningfully coordinating the different referent units in the fraction situations, were the ones consistent in their representations and reasoning, and in successfully establishing referential commutativity for multiplication of fractions. [For the complete proceedings, see ED585874.]