Teacher Preparation Programs must work towards not only preparing preservice teachers to have knowledge of classroom pedagogy but also must expand preservice teachers understanding of content knowledge as well as to develop higher-order thinking which includes thinking critically. This mixed methods study examined how writing shapes thinking and how writing in the content areas can be a tool to promote both critical thinking and learning new content material. This study focused on preservice teachers and utilized structured writing assignment tasks including surveys and rubrics to assess and measure progress throughout the semester. Research questions addressed in this study: 1) Does writing in the content area help preservice teachers learn new material? 2) Does writing in the content area translate to critical thinking for preservice teachers? and 3) If writing shapes thinking, to what degree does it shape critical thinking for preservice teachers? Overall, findings indicate positive correlations between writing to learn and progress towards critical thinking.