In 2003, the "ICT Curriculum Integration Performance Measurement" was developed from an extensive review of the contemporary international and Australian research pertaining to the definition and measurement of ICT curriculum integration in classrooms (Proctor, Watson, & Finger, 2003). The 45-item instrument that resulted was based on theories and methodologies identified in the literature review. This paper describes psychometric results from a large-scale evaluation of the instrument subsequently conducted, as recommended by Proctor, Watson, and Finger (2003). The resultant 20-item, two factor instrument, now called "Learning with ICTs: Measuring ICT Use in the Curriculum", is both statistically and theoretically robust. This paper should be read in association with the original paper published in the Computers in the Schools (Proctor, Watson, & Finger, 2003) that described in detail the theoretical framework underpinning the development of the instrument.