This paper presents the integration of ubiquitous computing systems into classroom settings, in order to provide basic support for classrooms and field activities. We have developed web application components using Java technology and configured a classroom with wireless network access and a web camera for our purposes. In this classroom, the students interact among each other and with the professor through an Internet-enabled personal digital assistant (PDA), using the different modules described in this paper. We include our evaluations about the performance and usability of the system in a computer science related course of the University of Tokushima, other practical uses including outdoor learning activities, and future research and development work. (Contains 2 tables and 10 figures.)