The question of whether single-sex or co-ed schooling has any impact on students' attitudes toward science is highly contested and warrants research from all corners of the world. This study adds to our current knowledge by investigating different attitudinal indices of Grade 9 science students (N = 356, M[subscript age] = 14.5 years) in single-sex and co-ed schools in terms of involvement in science instruction, enjoyment of science, value of science, engagement in practical work, influences of family, teachers, peers, and friends, interest in, and confidence for future participation in science. A total of 356 questionnaires was completed using a 43 Likert-type attitude questionnaire, and these served as the basis for data analysis in the study. The analyses indicated a relationship between gender and school type on students' attitudes toward science across all seven attitudinal dimensions examined. The findings revealed that: (a) attitudes toward science among students from co-ed schools were significantly lower than those of single-sex schools (p < 0.001) and (b) compared to boys in co-ed schools, girls in single-sex schools had a similar attitude toward science in terms of enjoyment, confidence, and future participation in science, and they were more engaged in science activities such as displaying experiments or doing small group activities. The findings also show that, in addition to students' personalities, gender, and other factors, there is a school factor involved in shaping their attitude toward science.