The article presents the results of the research of the properties of "collective" residual knowledge, invariant to the characteristics of individuals, academic subjects and tests, obtained as a result of a long-term integrated monitoring the quality of training at NTUU "KPI" for the period of 2005 -2011 years. The research covered about 50 000 students and over a thousand of subjects as well as the results of monitoring residues of students' knowledge at per-university preparation NTU "KPI" courses for the period of 1991-2011 years. Almost all regions of Ukraine were covered and more than 100 thousand people participated in it. As the result of the research the model of information academic flow and a quantitative assessment of modeling it are proposed. The structure of a long-term and short term knowledge at the stages of its life cycle are determined. The dependency between the level of a long-term residual knowledge and such parameters of learning process as the number of students in an academic group, amount of learning material and the level of initial training of students are assessed.