Frequent applications of short tests or quizzes during classes can be effective to enhance educational effects to students in universities. However, teachers may have to spend much time to prepare test materials before classes, and mark the test papers from students after them. In this paper, in order to reduce these loads of teachers, we propose a Web-based computer-scored test assistance system that consists of the five functions for problem generation & management, test generation & management, grading, subject generation & management, and learning profile management. By handling problems and tests separately where one test is composed of several problems, this system allows users to reuse existing problems and tests in various subjects by sharing them among teachers. Besides, by automatically generating test papers containing the randomly shuffled choices for each problem, it can prevent students from cheating by peeking at test papers of other students at neighbor seats. We implemented the system by extending our learning management system called NOBASU, and applied it to one class in our department, where the questionnaire result confirms the effectiveness of the system.