Teachers choose to supplement their curriculum for various reasons (Drake, 2010) and use online resources to search for and choose these supplements for their curriculum (Silver, 2022). TeachersPayTeachers.com (TPT) is a popular choice for online curriculum resources. TPT is a virtual resource pool that allows teachers to create and share resources so that other teachers can download those resources (for free or at a cost). In this investigation, I used the Teacher Curriculum Supplementation Framework (Silver, 2022) to investigate the features and use of Algebra resources from TPT. A qualitative content analysis of 40 of the top Algebra resources from TPT concluded that teachers primarily use TPT to search for supplemental activities in their classroom for extra practice and are focused on resources that will engage their students. Teachers found the resources to be aligned to standards and of high quality, in contrast to the assessment of researchers (Polikoff & Dean, 2019). Those responsible for creating and choosing curricula for use in classrooms should take note of the importance of engagement for teachers and how to incorporate more engaging activities into the official curriculum materials. Further research should investigate what specific features teachers associate with quality when searching for supplements. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]