Abstract
Social Constructivism which Ernest (1991) suggested apart from Radical Constructivism, is an important direction in research of mathematics education. The social context or situation in learning mathematics have been often neglected. For the first time, Gattegno pointed out the significance of learnig situation. But it was almost physical. Sociocultural one was little considered. Social Constructivism suggests the research on sociocultural factors in learning mathematics. And it is another possibility of Social Constructivism that it implys the consideration of learning aims. Therefore the main probolem is what are the basic theories in Social Constructivism. Ernest (1994) proposed two theories, Piagetian thery of mind and Vygotskian theory of mind. But I suggest adding situated learnig theory, especially "Legitimate Peripheral Participation" by J. Laveand E. Wenger. It 'takes a relatively radical position by attempting to avoid any reference to mind in the head (Cobb, 1994, p.18)', which is so different from Piagetian theory and a developed form of Vygotskian theory. Therefore it considers a learner and learners holistically and socially and regards their identity to learn as important. And it could contain the new third direction against indoctrination and constructivism in mathematics education.
