The article presents the structure, content and results of approbation of the C++ programming course developed for the 10th grade students of physics and mathematics profile and implemented as part of the academic subject “Informatics”. The aim of the course is to develop in the student not only knowledge and skills in programming, but also his algorithmic culture and programming culture as important qualities of a potential IT-specialist. This is facilitated by special control of educational process by the teacher, which consists in monitoring the activities of students in writing programs and timely correction of this activity. The assessment of the level of development of student algorithmic culture and programming culture relative to the basic level of their formation (when mastering the basics of algorithmization and programming in the 9th grade) was carried out on the basis of a number of criteria presented in the article. The results of approbation showed that the specially organized teacher activity makes it possible to increase the level of algorithmic culture and programming culture of high school students when studying the basics of programming in C++.