Research findings in the field of Mathematics Education emphasize that storytelling is an effective instructional tool in the teaching of mathematics, as it provides a meaningful context that attracts students' interest and makes learning a pleasant process. The use of stories and fairy tales in the teaching of mathematics motivates students to learn and provides students with an authentic context to understand mathematical concepts and procedures. It is a clear way to incorporate mathematics into other, broader cognitive domains and promotes mathematical discussion in the classroom. The main purpose of this study was to investigate the role that the use of storytelling can play in teaching fractions to third grade students. The study sample consisted of 76 third graders, who attended two primary schools in the city of Florina (Greece). This sample was divided into experimental (n=38) and control (n=38) group. In this study target-focused teaching stories were used. These stories were written in accordance with the objectives of a new Curriculum for rational numbers teaching. The study results showed that the use of storytelling had a positive effect on students' achievement in fractions, as the experimental group performed significantly better than the control group. The students who benefited most from the use of storytelling were those with medium, especially, with low performance. Finally, the use of storytelling had a positive effect on specific mathematical skills, such as comparing fractions, finding equivalent fractions, creating and manipulating representations and problem solving.