Assessment of elementary school students' knowledge about science is essential. Despite the existence of curricular materials and assessment tools for science content and concepts at all grade levels, there is very little information on how to assess the science process skills that students are expected to learn through science instruction. This paper describes the development of a framework for assessing science process skills among elementary school students. The assessment continuum was constructed by five elementary school teachers and one university science educator. Rubric sheets for assessing science process knowledge are appended. (WRM)