Fractions are troublesome for many children, especially students with learning difficulties and disabilities in mathematics. To address this serious educational concern, this article recommends the use of number lines to build fraction sense. Math activities that center on the number line build fraction concepts as early as third grade. A number line approach for teaching fractions is supported in the Common Core State Standards, and this approach has proved helpful for advancing low performing students' fraction understanding. This article provides examples of how to integrate the number line into fraction activities to address common fraction misunderstandings and to prepare students for later algebra courses.