Using graphic organizers to enhance students' science vocabulary and comprehension of nonfiction science text

The purpose of this research was to investigate the effectiveness of Frayer Model and the Hierarchical Organizer as a literacy strategy to improve ninth grade students' science vocabulary and comprehension of non-fictions text in Environmental Science course. The study implemented a sequential explanatory methodology design that included quantitative and qualitative instruments. The research sample consisted of one hundred and two (102) high school environmental science students entering the ninth grade for the first time. The two treatment groups each consisted of thirty-five (35) students, and the control group consisted of 32 students. Treatment group one used the Frayer Model; treatment group two used Hierarchical Organizer and the control group used the traditional teaching methods without the use of a graph organizer. The investigator taught both treatment groups and the control group to ensure reliability. The two treatment groups were taught using graphic organizers as the main lesson plan tool and the control group was taught using guided notes lecture with PowerPoint. A pretest and post-test were administered to each student. Student test scores were evaluated to determine whether knowledge gains differed between the treatment groups and the control group. It was found that the use of graphic organizer instruction was significantly better for student achievement when compared to the use of PowerPoint instruction and that there was much more interaction between student and teacher during the graphic organizer lessons. The delivery of the lesson by the use of graphic organizers seemed to promote more success than the use of the PowerPoint and lecture.