Students’ personality development refers to enhancing their social and emotional well-being, developing their communication and interpersonal skills, and preparing them for future academic and career responsibilities. The thinking process of the students influences their personal development, too. In this article critical, creative thinking, reasoning process was analyzed according to literature materials. Creative thinking steps and learning approach were examined, and the positive relationship find out between academic achievement and learning approach of students. The previous researches let us determine relation and affect between academic achievement and student personal development. This study can help the teachers, the researchers and school administrators who are working with students’ groups.