An instrument is presented for recording and analyzing student and teacher behavior in laboratory or activity-centered vocational education classrooms. The instrument uses categories of behavior, such as: (1) asks extended thought questions, (2) shows or illustrates, and (3) management of lesson, for teachers; and categories such as: (1) asks questions, (2) reads lesson-related material, and (3) gets supplies or moves around the room, for student behavior. The categories are recorded using single-letter codes, along with codes to indicate to whom the behavior is being directed and the sex of the person to whom the behavior is being directed. This document describes the development and validation of the instrument, and gives descriptions of and rules for use of the categories. (BB)