This study was designed to determine whether student writing, after completing restructured curricular activities, has an effect on overall learning. During this study, students in a central Iowa high school biology classroom were introduced to the Science Writing Heuristic (SWH). The SWH is a writing model that moves away from using writing in science to demonstrate understandings toward aiding students in constructing knowledge regarding scientific concepts and ideas. It is composed of two templates, student and teacher, to aid in structuring writing activities during laboratory investigations. The study was performed during two curricular units, cells and genetics, with three big ideas the focus of each unit. Data was collected through pre and post tests for each unit and analyzed using both ANOVA and ANCOVA tests to measure both gender and achievement level differences. Results from the study show initial significant differences between gender and achievement levels, but after using the SWH for one unit, those significant differences disappear. Discussion of trends in results, limitations of the study, and implications for future use are presented.