The article describes the organisation, the progress and results of the educational experiment with the use of a programmed text and a teaching machine for the teaching of chemistry in the 8th grade of the Elementary Nine-Year School. The results show that the basic pre-requisite for a successful application of programmed instruction is the ability of consciously reading the text. If this pre-requisite is fulfilled, the experimental class shows distinctly better knowledge than the check-up class. The text does not programme only verbal theorems, but also pupils’ experiments, from which the next question is derived. The programme is ramified (Crowder’s system). The teaching machine is adapted for putting in a ramified programme. The progress and results of the experiments with a programmed text and the machine show that this form of work is especially suitable for average pupils and for those just below average.