The periodic table and the periodic system are central to chemistry and thus to many introductory chemistry courses. A number of existing activities use various data sets to model the development process for the periodic table. This paper describes an image arrangement computer program developed to mimic a paper-based card sorting periodic table activity. The advantages of the computer format are described, with a key feature being the ability to playback students' actions. Being able to observe students working with the data as well as viewing their final answer can allow instructors to identify areas of student difficulty and structure classroom discussion of data analysis and periodic trends to address misconceptions and build on students' work. Comments on the successful implementation in college general chemistry are included. (Contains 3 figures, 1 table, and 1 note.)