In 1987-88, 1990-91, and 1993-94, the National Center for Education Statistics' Schools and Staffing Survey (SASS) presented teachers in public schools throughout the United States with a list of school-related problems and asked for ratings of their severity in their schools. This brief examines two safety-related matters, physical conflicts among students and weapons possession, and presents the percentages of public school teachers who considered these matters as moderate or serious in their schools. The data show that from 1987-88 to 1993-94, increasing percentages of public elementary and secondary school teachers reported physical conflicts among students as moderate or serious problems in their schools. The percentages of public secondary school teachers reporting weapons possession as a moderate or serious problem in their schools nearly doubled from 1990-91 to 1993-94. From 1987-88 to 1993-94, teachers in public schools with more than 750 students consistently reported physical conflicts among students and weapons possession as moderate or serious problems more frequently than did teachers in schools with fewer than 150 students. The data suggest that teachers viewed public schools as less safe in 1993-94 than they did in 1987-88 or in 1990-91. At both the elementary and secondary levels, teachers' reports of physical conflicts among students and weapons possession were at their highest levels in 1993-94. Although more frequently reported at the secondary level over time, these problems were cited more often in large versus small schools at both levels. One table and one figure are included. (Contains eight references.) (LMI)