This article is based on the author's experiences as a second-year teacher at a small private school teaching all sections of Geometry and Algebra 2. Working with the same students in both courses, the author was aware of each one's levels of retention and execution of Algebra 1 concepts before the beginning of the year. The author often noticed the specific skills that a student struggled with during class, but, to provide concrete data to back up informal findings, wanted to find a way to record each student's understanding of fundamental skills. The author hoped that addressing gaps in prerequisite skills would allow students to focus on new concepts, get correct answers more often, and gain confidence in their mathematical abilities. With this objective in mind, the author chose to explore the use of preassessments to determine Algebra 2 students' level of understanding of key algebraic prerequisite skills. The resulting data did not affect students' grades but were instead used to inform teaching practices. In this article, the author, a teacher, reflects on the importance of determining what constitutes prerequisite material and the value of limiting the number of skills assessed. A bibliography is included.