The study focuses on one of basic elements of education in natural sciences: scientific educational experiment. In the first part of the text, the authors discuss the role of educational experiment in the teaching of natural sciences and explain the 3A procedure that was used as an analytical approach. The second part provides an analysis of a selected teaching situation from the perspective of cognitive activation of students. The text aims to analyse the content construction of scientific experiment and its didactic use in teaching with respect to the quality of instruction. It aims to provide transdidactic abstraction to the domain of natural science education. The analysis found instances of didactic formalisms that threaten the quality of instruction; obscured learning and assumed learning. Such formalism are the results of insufficient didactic analysis of the deep structure of teaching and stand in way of the development of students’ scientific literacy. Alterations are suggested that aim to eliminate formalisms and help support the cognitive activation of students through didactic integration of structural components of the scientific experiment: hypothesis - experiment - observation - conclusion.