The article describes the possible application of the principles of cultural-historical approach and activity theory to the inspection of toys and play environments. A children’s playground is treated as cultural means or artifact created by adults for starting a child’s activity. In terms of cultural and historical psychology, psycho-pedagogical analysis of a playground is based on the identification of the play value level and the compliance with the objectives peculiar to the age. Analysis and design are based on the understanding of the playground as a single space, where each element has the potential for any children’s development activity — games, communication, experimentation, etc. The following criteria of psychological and pedagogical inspection are identified and well-grounded: the principle of orientation to age-related peculiarities, the principle of high play value, the principle of transparency of objects, the principle of supporting acceptable risk, the principle of taking account of visitors’ activity levels, invitation to dialogue — the principle of dialogueness. The use of these principles in the course of designing playgrounds is illustrated by examples. These show that the conceptual apparatus of cultural and historical psychology may be used not only to explain the mechanisms and forms of mental development, but also for the analysis of particular conditions of a child’s mental development and design of play environments.