Abstract : The present study was conducted to investigate the effectiveness of using a task based program taught through the discussion method to improve secondary stage students' argumentative paragraph writing skills and self-steam. Ninety two students were randomly selected and divided into a control group and an experimental one. The experimental group was trained in a task based program taught through the discussion method. The control group was instructed a course of these skills through the conventional method of teaching. Instruments of the present study included an argumentative paragraph writing skills test and a self-steam scale. Analysis of data obtained on the post tests revealed that the experimental group surpassed the control group in both the argumentative paragraph writing skills test and the self-steam scale. The suggested training program was found very effective in improving the students argumentative paragraph writing skills and it was found very effective in positively improving the students' self-steam. Key words:  task based program, argumentative paragraph writing skills, students' self-steam