A study was conducted to examine the impact of classroom arrangement (open versus traditional) and tidiness (messy versus neat) on observers' expectations about a teacher. A heterogeneous sample of college students was shown color slides of vacant elementary classrooms varying in terms of these two dimensions and asked to indicate their impressions of the teachers and the pupils who used the rooms. A multifactor, repeated-measures analysis of variance was conducted. Findings indicate that observers form strong impressions about a teacher's behavior and personality based on the neatness of the classroom. In addition, furniture arrangement had a significant impact, with open classrooms leading to more positive impressions of a teacher's responsiveness and creativity. (SW)