This article analyzes the use of a dichotomous key as a technique for identifying plants and animals in different author lines of biology textbooks of different years (from the first Biology textbooks in 1992 to new generation textbooks according to an updated curriculum). The priority of new textbooks in almost all disciplines is education through activity, so mastering the methodology for using the dichotomous key is invaluable. The significance indicator is determined by the methods of schoolchildren in identifying systemic signs of various groups of organs and the formation of practical skills in choosing the taxonomic position of given plants and animals.

A thorough analysis of the textbooks of the new generation (according to the textbook of Biology 2017, grade 7, authors E.A. Ochkur, Zh.Zh. Kurmangaliyeva) showed a discrepancy, and methodological errors made by the authors when using the dichotomous key were also identified. All these shortcomings make it difficult to master the methodology and the formation of key competencies