"Social Life and Moral Virtues" is a major subject of moral education programs in Taiwan's elementary school. Value clarifying approach in re-cent years has been adopted in the moral education programs with the purpose of cultivating children's moral behaviors. This study set out firstly to sketch the constitutive elements of moral behaviors and the context of moral instruction by way of analzing how we formulate our value systems. Against the background of this sketch, the three evaluating systems of value clarification - cognition, affection and action - are then examined to see what level they have to be and how effective they can be in helping school teachers to act as models for children. Moreover, based on the field experiences of conducting the value clarifying approach in "Social Life and Moral Virtues" some feasible strateges of moral instruction are offered for el-ementary school teachers.