This paper describes the development and validation of a set of three assessment instruments that can be used to assess students' progress on the energy concept (ASPECt) from fourth through twelfth grade. Rasch analysis techniques were used throughout the development process to guide the construction of an item bank and the selection of items for inclusion on the instruments. Rasch analysis techniques were also used to validate the instrument and design support materials to aid in the interpretation of student performance. A cross-sectional analysis was performed to determine the match between the instruments and students and revealed that currently the difficulties of intermediate and advanced instruments are greater than the average performance level of students in grades four through twelve. Wright maps and option probability curves were created to help users interpret student performance. [Paper presented at the AERA Annual Conference in New York, NY, April 13-17, 2018.]