Technology offers many opportunities for educators to support teaching, learning and assessment. This paper introduces a project to design and implement a virtual environment (SAVE Science) intended to assess (not teach) middle school students' knowledge and use of scientific inquiry through two modules developed around curriculum taught in middle schools in Pennsylvania, U.S.A. We explore how the concept of "presence" supports these efforts, as well as how Piaget's theory of developmental stages can be used as a lens to understand whether these students achieved presence in the modules. Findings are presented from a study looking at 154 middle school students' perceived sense of presence in a virtual world developed for the SAVE Science research project as demonstrated through a post module survey and a post module discussion with their teacher. Age and gender differences are explored. In addition we use content analysis, as described by Slater and Usoh (1993), of student talk in the post module discussion transcripts to identify levels of "presence." In the end, participating seventh grade students demonstrated achieving some level of presence, while the sixth grade students did not. (Contains 5 tables and 3 figures.)