This study concentrates on investigating teaching methods with which students of a commercial high school, located in a rural district, can improve their attitude toward mathematics. To begin with, this study examines the causes which make the students take negative views against it through a survey of their current attitude toward mathematics; offers a special class for them to develop a positive attitude toward it: and then, figure out how much they change their academic attitude within the class and how much they improve their academic achievement as well. The results can be summarized as follows: First, the experimental groups showed terribly negative attitudes toward mathematics, and their academic achievements were very low compared with students of academic high schools nearby, Second, thanks to the special class given to improve their attitude toward mathematics, the experimental groups ended up taking a meaningful positive attitude toward it and developing their academic achievements in the subject. On the other hand, the controlled groups without any chance to receive special lessons remained unchanged. Therefore, it is indicated that a special lesson, properly provided, would play an important role to improve students' positive attitude toward mathematics and develop their basic academic achievements.