This paper describes an approach to extending the learning experience using a Web-CAI system incorporated with MATHEMATICA, which is an advanced calculating software widely used in science and engineering fields. This approach provides the possibility of extending access to the courses that students have learned at school. We can use variables in mathematical formulas so that different problems can be shown to students. At the same time, we can also use algebraic formulas. In addition, applying MATHEMATICA to the given process for the answer automatically makes the answer of the problem. And two types of the answer expressions are acceptable which are filling in text by keyboard and selecting by click. This paper presents the design for the system and its specific implementation, and the technical solving scheme. At the end of this paper, the learning evaluations and the problem-editing interface design are discussed.