In the process of transition of Russian organizations of secondary professional education to educational standards of the third generation educational process is reduced to formation of students’ competences. This article presents methodology of creating integrated lessons of natural-science cycle (for example, in physics and informatics). These lessons are constructed on the basis of interdisciplinary integration and focused on task solution. The main purpose is to teach students how to solve particular tasks in physics with the use of informatics, in particular on the basis of algorithmization and programming (Pascal language). Didactic conditions, which are the basis of the algorithm of designing corresponding tasks, are described in this article. Structural components of the integrated lessons created on the traditional principle are marked out. During the research we observed that realization of all stages of the corresponding lessons in practice allows the teacher to create educational process over the borders of disciplinary basis. This approach helps to form generalization of knowledge. Being one of the most optimal forms of education, an integrated lesson allows students to solve various educational and professional problems in non-standard situations and stimulates their cognitive activity and their involvement in the process of education and their responsibility for the result which promotes an intensification of educational process.