Fraction is one of basic ideas for students to support further learning of mathematics. For instance, in the study of decimal students should be able to change a fraction term to a decimal and turn a decimal to a fraction. In the study of real numbers, especially rational numbers, students need to learn the concept of fraction before. From my direct experience, for children, it is not easy to learn the concept of fraction. Its meaning and its processes of calculations with operations differ from what they learned (the concept of whole numbers). The processes of fraction calculations, especially addition or subtraction and division, are more complicated. These seem to be students’ difficulties when they learn the concept of fraction.