This paper presents staff development implications for elementary and secondary school teachers which were gleaned from assessments of classroom teachers' testing needs, resources, practices, and proficiencies made by 586 supervisors and principals and 326 teachers in an Ohio study. These assessments included direct analyses of teacher-made tests as well as perceptual assessments of teachers' testing needs and proficiencies. It was generally agreed that testing proficiencies were not adequate to meet classroom needs. Analyses revealed that typical teachers gave 50 or more formal teacher-made tests each year, for which they wrote most of their own questions. Matching exercises on teacher-made tests were particularly prone to error. Most teacher-made tests, except in mathematics and science, functioned primarily at the knowledge level. Administrators' and teachers' perceptual assessments of teachers' testing skills were negatively correlated with the results of direct analysis of teacher testing skills as displayed in their teacher-made tests. Standardized tests were reported to be less needed in the secondary than in the elementary grades. Schools had very limited support services, such as typing and duplication, available to support the testing responsibilities of their teachers. Two tables present study data. (Author/SLD)