The Wireless Online Tutoring System (WOTS) is a web-based, synchronous groupware system that has been developed to facilitate student collaboration in group projects. It supports interactive and collaborative structured-diagramming and is equipped with group awareness features such as remote cursors, locking, and textbased instant messaging. Users can access WOTS from both personal computers and handheld devices, allowing it to be used in wireless classrooms or distributed environments. Tests on student software design projects validate the ability of WOTS to support student collaboration in group projects, and show that its architecture is scalable and reliable. Its performance is expected to improve as more powerful handheld devices and wireless technologies come on to the market.