Academic achievement is an important factor affecting students' life in very diverse aspects, including values, school life, and career decision as well as self-concept, and is also considered to be one of the most important goals of school education. In addition, students' academic performance is regarded as an important predictor of the social class they will belong to and the role they will play in society during adulthood. For this reason, teachers in schools make great efforts to help students improve their academic achievement and those involved in education also try to identify diverse variables affecting academic achievement and apply their results to the teaching-learning process with the objective of devising a plan to help students improve their academic achievement. To determine what causes differences in academic achievement among individual students, many educational experts strive to find out a clue to it among genetic and environmental factors.