The purpose of this study was to investigate the effects of class type, coeducational or same-sex, on the self-efficacy of middle school girls in a unit of volleyball. Four intact certified physical education specialists from two Middle Schools were used in the study. All of the teachers were female. In two of the classes, students were split out according to gender with males being taught by one instructor and the females being taught by the other instructor. For the coeducational classes, the students were randomly assigned to either of the teachers, with boys and girls evenly divided between the two classes. Essentially two new classes were created at each school. Quantitative and qualitative methods were used for the study. Two questionnaires were administered to the students. Analysis of data from the questionnaire showed the student variables that were measured quantitatively for determining girls' self-efficacy for learning volleyball were found to be significant at the 05 level, favoring girls in single-sex environments. Data from the post-intervention questionnaire and student and teacher interviews were analyzed to provide insight into student preferences for these contexts. It is concluded from the qualitative data that single-sex classes have a more supportive learning environment, and have better conduct than coeducational classes. / Ed. D.

Failure of high school students on the Senior School Certificate Examination (SSCE) in Nigeria is severely limiting the number of students qualified to enroll in college. The purpose of this multiple case study of 6 high schools in southern Nigeria was to describe principals' perceptions of student performance on the SSCE and the principals' influence on school climate, teacher expectations and approaches, and student performance. The theories of reasoned action and planned behavior provided the framework for the study. The research questions focused on the extent to which principals developed and sustained a school climate that supported positive outcomes. Qualitative data on principals' perceptions were gathered using semistructured interviews with 48 lead teachers and 6 principals. Data derived from textual transcripts, document reviews, and the results of a cross-case analysis were categorized and developed into themes such as student-related issues, family socio-economic status, and the education system. The results showed students' socio-economic challenges and principals' concerns about the SSCE. Effective principal leadership and positive school climate were essential to enhancing teacher expectations and approaches and were linked to improved student performance in high-performing schools. These findings and implications can inform professional development programs for principals that emphasize a holistic approach, support students' socioeconomic experiences and academic needs, and gather parents' views on best practices. The potential for social change includes improved principal leadership and contributes to higher achievement on the SSCE and increased college enrollment.