In recent times there has been considerable commentary regarding the need to enhance mathematical assessment as evidenced by Numeracy, A Priority for All: Challenges for Australian Schools(2000). This emphasis on assessment is timely because although the mathematical reform movement has produced much-needed improvements in both curriculum and instruction, changes in assessment have not kept pace (Firestone & Schorr. 2004; Morgan, 1998). As Ridgeway (1998, p.2) states, ""As an issue of policy, the implementation of standards-based curricula should always be accompanied by the implementation of standards-based assessment. In fact, incremental change in assessment systems will foster concurrent improvement in professional and curriculum development.""