The construction of the student\'s knowledge, namely the student modeling, is a core component used to develop intelligent education systems in e-learning environment. However, existing e-learning systems have many problems to share the knowledge in heterogeneous student models and distributed knowledge bases. The accumulated knowledge cannot be used or shared without a great deal of difficulty, because the methods of the knowledge representation are different in each e-Learning systems. In order to share this knowledge, existing education systems have to reconstruct the knowledge bases. In order to overcome these problems, we propose a new a Case Markup Language(CaseML) based on XML. The CaseML provides method that the distributed e-Learning systems can have the advantage of easily sharing and managing the students knowledge base. Moreover the students can generate and share the case knowledge to use the communication protocol of agents. In this paper, we have designed and developed a CaseML by using a knowledge markup language. Furthermore, in order to construct the intelligent e-Learning systems, we have done our research based on the design and development of the intelligent agent system.