GeoGebra is a dynamic mathematics software, it is very helpful for teaching mathematics. In Turkey, particular for topic “Parabola”, Reis, Z. A., Ozdemir, S. (2010) used GeoGebra to teach Parabola and outcomes of students in experimental class were better than the ones of control class. Learning from Reis and Ozdemir, in Vietnamese context, we want to verify whether teaching Parabola by guided discovery with GeoGebra in schools could be more effective or not in comparison with teaching Parabola with traditional methods of teaching. The results of the study also showed that Vietnamese students learned in dynamic environment of GeoGebra obtained the good learning outcomes of mathematics.