The tele-blackboard is an audiovisual system, the core of which is a tableau on which is put a normal piece of paper. The paper is written on with a pencil that goes with the tableau, and the visual information is transformed into narrow banded signals which are sent simultaneously with a verbal explanation by normal longwave radio transmitters. Visual and verbal information are thus transmitted across long distances at very low cost and can be received by normal radio and television receivers with special adapter. The tele-blackboard was designed for instruction in developing countries. It requires prior preparation of short, well organized teaching phases and high concentration by the pupils, while at the same time releasing the teacher from the anxiety of being on television. Other advantages offered by the tele-blackboard are the opportunity its use provides to develop original and modern forms of fundamental education, the reduction of loss of information which verbal information alone is subject to (particularly when the language used in the presentation is a second language for the students), and the capacity for producing dynamic content and concepts. (SH)