Students in developmental math classes have been documented to struggle with arithmetic. This dissertation research was a response to the calls in the literature to qualitatively understand what students are learning in a classroom. Number sequences have been well researched to document the connection of student understanding of math in elementary grades. This research uses number sequences to document the multiplicative reasoning of students and extends the literature to students in a developmental math class. I documented the reasoning of 14 students in a developmental math class in an open enrollment college and demonstrated varying levels of multiplicative reasoning as characterized by their number sequences. Students who performed the best in the class had more sophisticated number sequences while lower performing students had evidence of less sophisticated number sequences. This research adds to the field by providing researchers and instructors with evidence for the import of understanding number sequences as a way to understand student struggles for the purpose of supporting their learning. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]