Augmented Reality (AR) is a tool increasingly available to young learners and educators. This paper documents and analyzes the creation of an AR app used as a tool to teach fractions to young learners and enhance their engagement in the classroom. As an emerging technology reaching diffusion into the general populace, AR presents a unique opportunity to engage users in the digital and real world. Additionally, AR can be enabled on most modern phones and tablets; therefore, it is extremely accessible and has a low barrier to entry. To integrate AR into the classroom in an affordable way, I created leARn, an AR application intended to help young learners understand fractions. leARn is an application intended to be used alongside traditional teaching methods, in order to enhance the engagement of students in the classroom. Throughout the development of the product, I not only considered usability and design, but also the effectiveness of the app in the classroom. Moreover, due to collaboration with Arizona State University Research Enterprises, I tested the application in a classroom with sixth, seventh and eighth grade students. This paper presents the findings from that testing period and analysis of the educational effectiveness of the concept based on data received from students.