This study presents the preliminary qualitative results of a larger mixed methods study. The qualitative phase utilized task-based clinical interviews to examine the non-symbolic and symbolic linear generalizations of middle-grades students. This investigation identified similarities and differences in the students' generalizations, and interpreted these distinctions within the number sequences framework, which describes a hierarchy of numerical reasoning stages. Participants included 14 students in grades 6 through 9 who operated at 3 distinct stages of numerical reasoning, as framed by the number sequences. Findings indicate that the number sequences were related to students' generalizations, in that students with more sophisticated numerical reasoning produced more sophisticated generalizations. The analysis relates students' generalizing behaviors to the mental operations that define each of the three number sequences under examination. This study demonstrates the importance of supporting students' numerical reasoning as a means of preparing them to reason algebraically in the middle grades, contributes theoretically to an understanding of the relationship between numerical reasoning and generalizing, and suggests instructional strategies for engaging students in generalizing.