ABSTRACT: An important factor in acquisition of language skills is the intensity of student's participation under the guidance of the teacher. During the formative phase of a language course, the conventional classroom procedure usually splits equally the time between teacher and students. The CLIS experiment was based on the assumptions that electronic media offer the opportunity to record linguistically and methodologically well-organized teaching materials, to transmit them to the learner in greater quantity and in a more constant manner than possible in the conventional classroom setup, and thus to increase significantly the student's active participation. The long-range experiment confirms the assumption that the use of the classroom laboratory coupled with proper teaching materials significantly improves language acquisition and enhances the role of the teacher as the manager of learning.