The subject of the paper presents establishing basic characteristics, forms and levels of knowledge interconnectedness in teaching, especially in mathematics and biology teaching. The analysis was realized by considering basic theoretical views in this field, as well as by establishing features and levels of knowledge interconnectedness in the context of teaching programs, textbooks and teaching process, and in students. Some theoretical assumptions are based on the analysis of theoretical views of the problem of knowledge interconnecting in teaching. It was established that traditional, empirical conception of the process of knowledge attainment, connecting knowledge and knowledge systematization in teaching is mostly presented in didactics and methodologies of particular teaching subjects. Within the framework of the theory of developmental teaching, established by Russian psychologist Davydov and followers, there is concept of "knowledge systematism", as one of the main concepts which belongs to the conception of teaching activity. [This article is a result of the project "Education for Knowledge-Based Society" No. 149001 (2006-2010), financially supported by the Ministry for Science and Environmental Protection, Republic of Serbia.]