Changes in the relative academic achievement of Florida's black and white children over the last 13 years during which desegregation was taking place are investigated. The availability of achievement data for the entire black and white population, along with the 13-year time span between observations are seen as principal advantages. Data show that the academic achievement gap between white and black children was smaller in 1974 than in 1961. The amount of decrease in the gap is stated to be small, yet of practical significance for the four subject areas examined: reading, vocabulary, math computation, and math problems solving. Of these areas, convergence in the black and white distribution was greater for math computation than for the othersubtest areas examined. The use of different tests in 1961 and 1974 is held to make assessment of changes in the absolute performance level of black or white children difficult. It is suggested that the study be viewed as an evaluation of a social action program rather than a scientific experiment. (Author/AM)