Smart learning is becoming the most important trend of modern education and the important part of many countries' development strategy. Based on the theory of knowledge aggregation, the knowledge value adding issue in smart learning environment was discussed. After reviewing related literatures, the knowledge aggregation nature and the non-liner learning character of smart learning were explored and a smart learning model was set up. Further, an individual learner's knowledge achievement model and a knowledge extraction and integration model were set up to get the knowledge value adding description. The example of Khan Academy was illustrated to provide an explanation of the realization process of knowledge value adding processes in smart learning environment.