An attempt was made to measure the language behavior of students in the upper elementary grades. The procedures and results of research in the following five areas are described in this report: (1) Relationship between the Linguistic Ability Test and the written discourse of fourth and sixth graders; (2) Comparisons of the discourse of fourth and sixth graders and of males and females; (3) Analysis of the effects of color and abstractness of pictures and of the specificity of instructions used in obtaining written discourse samples; (4) Comparisons of written discourse rated good, average, and poor; and (5) Comparison of oral and written discourse. (AG)