The first phase of a study to assess York County's new open plan schools is reported in this document. The study focused on the behavioral outcomes for students exposed to the open plan schools' programs. Three control county elementary schools were matched with the four open plan schools on age, socioeconomic conditions in attendance areas, and general geographic location. Students were randomly selected from these schools and observed as unobstrusively as possible during an entire school day by members of the observation team of seven principals and two master teachers. Observation results indicated a trend for these behaviors to be more readily observable in open plan schools than in the control schools: (1) pupils initiate activities that reflect their personal interests and these activities are given a chance to flourish in the day's activities; (2) pupils make (generally) good use of opportunities to display personal responsibility; (3) cooperative planning (teacher-teacher, teacher-pupil) takes place, and (4) pupils demonstrate the spirit of inquiry by raising pertinent questions. The document contains 10 representative cases out of the 18 made and the 15 completed for the study, a selected bibliography, an explanation of the study methodology, and the principals' statement of the open plan schools' common purposes. Data from all 15 completed case studies are included in various summaries in the concluding chapter. (Author/MLF)