We are presenting an interactive course on speech synthesis which is designed to support the education in speech communication. In the basic section, the fundamental principles of speech synthesis are explained. To explore a complete text-to-speech (TTS) system, the user is provided with access to the Dresden Speech Synthesizer DreSS. The user may type any text, and he may observe how the system processes the text from the first linguistic preprocessing until the acoustic synthesis. A further section is devoted to the crucial problem of correct segmentation of the speech elements used for the concatenative synthesis. The user may select his own diphone segments from a given speech data base. The quality of the segments may be evaluated acoustically, and hints are given to avoid errors in cutting. Thus, the user will learn how to select the segments with good quality. The course is written in HTML and Java and is designed for Internet application.