To understand and assess how early adolescents use their social perspective taking (SPT) skills in their consideration of social problems, we conducted two studies. In study 1, we administered a hypothetical SPT scenario to 359 fourth to eighth graders. Modeled on the linguistic pragmatics of speech acts, we used grounded theory to develop a functional approach that identified three types of SPT acts: (1) the acknowledgment of different actors, (2) the articulation of their thoughts and feelings, and (3) the positioning of the roles, experiences, or circumstances that influence how they resolve problems. Study 2 tested the validity of an expanded instrument, the Social Perspective Taking Acts Measure, with 459 fourth to eighth graders. We confirmed the structure of the construct with a fully saturated confirmatory factor analysis, with factor loadings in the range of .62 and .71, and a factor determinacy of .90. We obtained evidence of criterion-related validity by successfully predicting that girls and older participants would exhibit better performance than boys and younger students, and that SPT would exhibit a negative association with aggressive interpersonal strategies, a positive but moderate association with writing, and non-significant associations with academic language, complex reasoning, and reading skills.