Apply GeoGebra to develop digital materials of angle concept for the fourth grade students

Angle is one of the elementary geometry concepts. This research adopts ASSURE Model to utilize GeoGebra to develop virtual manipulatives of Angle concepts, and conducts a learning experiment to verify its usefulness on the fourth grade mathematics angle teaching. After experiment, the research surveys students' attitudes and learning styles, and employs experienced teachers to assess these digital materials. The result of evaluation shows that the digital materials are useful for the learners and can be applied on classroom teaching. On the other hand, the students' math attitudes are positive, and they show high interest on operating and learning the materials. The virtual manipulatives made of GeoGebra can fit students with different learning styles, and improve the angle concepts of students.