There has been a prolonged tendency of the gender gap in interest, participation, and achievement in science worldwide. This article explored the gender gap in achievement of science; revisited the possible causes of gender gap in interest, participation and achievement in science; and revisited the suggested remedy measures in a science classroom. The information for the study was collected through a survey of a variety of 48 written sources. The study revealed that there is a significant gender gap in achievement in science in secondary schools in Tanzania. The responsible factors include male-oriented curriculum materials, patterns of classroom interaction, teaching, and evaluation; parents and teachers' lower expectations for girls' achievement in science; and socialisation of girls into dependence, nurturance, and passivity. The recommended solutions include the promotion of gender-responsive curriculum and practice.