Developing a positive relationship with mathematics in early elementary is vital for success in future mathematics education. Students who do not develop an understanding of mathematical number sense in early grade levels struggle to make connections in later courses. Mathematical discourse sessions, specifically Number Talks, encourage students to develop efficient strategies, and learn to explain their thinking verbally. This study sought to answer the question: Does engaging elementary students in mental math Number Talks and implementing mathematical discourse strategies on a regular basis increase their mathematical fluency and success on the NWEA MAP Math Assessment? Implementation of Number Talks took place with a classroom of 21 third-grade students at Bunker Hill Elementary School, located in Middletown, Delaware, from September 2020 through January 2021. The research found an increase in student scores on Acadience Math Assessments and the NWEA MAP Math Assessment. The study showed student growth, and was similar to findings found in studies conducted elsewhere. There were several limitations to the study due the COVID-19 Pandemic, causing the intended Implementation Plan to be adjusted. Implementation of Number Talks in additional classrooms, other schools, and other teacher-model classrooms over a more extended period may still show growth, but should be completed for more accurate conclusions to be developed. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]