Present large-scale assessments require the use of item formats, such as multiple choice, that can be administered and scored efficiently. This limits competencies that can be measured by these assessments. An alternative approach to large-scale assessments is being investigated that would include the use of complex performance assessments. As part of this research, a set of essential middle-school science competencies that go unassessed by large-scale assessments was identified, based on Florida's current Sunshine State Standards. Each competency then becomes a starting point to establish observable evidence that is appropriate for determining competence and, in turn, tasks students can be asked to perform that are consistent with the needed evidence. Competencies are grouped within categories--Nature of Science, Earth and Space Science, Physical Science, and Life Science--that correspond to the four disciplinary areas used, for instance, in formulating the Common Core State Standards in science. The present paper lists and also describes the process used to identify these unassessed competencies. [Contains 1 footnote. This paper was prepared by the Center for Advancement of Learning and Assessment, Florida State University.]