The objective of this work is the acquisition of knowledge on the menstrual cycle. The research is carried out on a population of 176 pupils from four different high schools in Split. Each class involved in the research has been divided in two groups. The first group was defined as „the control group“, and the latter as „the experimental group“. The pupils involved in the research from both groups had the identical initial test before the lecture. The initial test consisted of eight assignments, and the task of the initial test was to determine the foreknowledge of the pupils on topic of the female reproduction system and the menstrual cycle. The average results of the control group were 50,78 %, and from the experimental group 57,68 %. After the lessons were conducted by standard teaching and heuristic teaching methods, the closing test was given to the pupils. The closing test consisted of eight assignments which were correlated to the diagram shown in the first assignment. There was a total of four different closing test groups given to the pupils, while the differences between them were only in the length of the menstrual cycle shown in the first assignment diagram. The average results of the closing test of the control group were 48,47 %, and of the experimental group 54,75 %. According to expectations, the female students have shown better knowledge on the topic when compared to male students. In the initial test of the control group, male students have managed to solve the test with an average result of 45,83 %, while the female students had an average result of 54.27 %. Male students have solved the closing test with an average result of 40,90 %, while the female students had 53,81 %. In the experimental group, the female students have also shown better knowledge on the subject. The initial test average result of the female students was 60,95 %, while the male students had 50,51 %. The closing test average result for the female students was 56,38 %, and for the male students 48,02 %. Since the results of the initial and the closing tests were poor, it is evident that the common approach of teaching biology in the classes does not involve graphical or figurative demonstrations. Statistical analysis has shown that the experimental approach shows better results, however, the differences were not statistically significant. The main conclusion of the research is that the common teaching approach needs to be changed.