Approaches to definition of a level of state of health of students are shown. 94 students (48 girls and 46 youths) of basic medical group took part in an experiment. The state of the cardiovascular system was probed on indexes by frequencies of heart-throbs, arteriotony, index of Robinson, adaptation potential of circulation of blood. It is marked that at the beginning of school year students have a low level of functioning of the cardiovascular system. At 73,5 % girls and 62,2 % youth is expose tachycardia. At 8,2 % girls and 26,7 % youth is expose the enhanceable norm of systole arteriotony.