This study was conducted to explore US elementary teachers' perceptions of their experiences using rubrics as a tool for student self-assessment and metacognition (assessment for learning) to improve elementary students' achievement and their instructional decision-making at a private American elementary school in South Florida. The constructivist learning theory by Piaget (1970) and Vygotsky (1978), which emphasized that knowledge is best gained through the interaction of experiences and ideas in one's mind and the interaction with others, framed the study. Three semi-structured interviews were conducted with eight elementary teachers: three third-grade teachers, three fourth-grade teachers, and two fifth-grade teachers. Using thematic analysis, the following four major categories emerged: (1) teachers' conceptualizations of using rubrics, (2) the reality of teachers' implementation of rubrics, (3) challenges faced by teachers in using rubrics, and (4) teachers' propositions to navigate the challenges. The findings of the study indicated that even though all teachers had positive conceptions and awareness of the possible effectiveness of rubrics as a self-assessment tool on students' learning and instruction, this did not necessarily translate to the teachers regularly and extensively enacting them in all contexts and all grade levels. The study also discussed the challenges elementary teachers faced when using rubrics, leading to them being reluctant to implement rubrics for self-assessment in elementary classrooms regularly. This study aimed to address the gap in qualitative research concerning elementary teachers' perspectives on the utilization of rubrics for student self-assessment. The findings of the study have implications and recommendations for the effective design and implementation of rubrics in elementary classrooms to better prepare teachers and support students' 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.]