On the occasion of the 90th anniversary of the birth of P. P. Blonski the article deals with his conception of the work school on the basis of his “Work School”, published in 1919. It shows how Blonski sees the individual stages of the work school and the work in it, how in the work school of the second* stage he stresses the link of education and industry and the education of the builders of a socialist society. On the basis of a description, Blonski’s conception of the work school is then assessed. The article points to the special situation in which Blonski formed his conception, and it stresses that he could neither use Dewey’s nor Kerschensteiner’s conception. It critically assesses that in his conception Blonski overestimated the educational influence of nature and primitivism, Blonski’s efforts to abolish classes, subjects and lessons are explained by his endeavours for concentration, and the questionability of teaching based only on random activities, thus arising, is pointed out. In the second stage of the work school Blonski’s industrialism and revolutionaly trend of the work school are positively assessed. On the whole Blonski’s conception of the work school is assessed as the first completed Marxist conception of the school for the socialist society. In conclusion the present state of solving the problems of work education in the socialist school and pedagogics is pointed out.