THE EFFECTS OF VOCABULARY INTERVENTION ON NINTH GRADERS' UNDERSTANDING OF PLATE TECTONICS

A study of the effects of vocabulary intervention techniques on student comprehension of plate tectonics was undertaken with ninth-grade earth science students enrolled in a high school in rural south-eastern Ohio. Fifty-four students were randomly assigned to three different treatment groups exposed to 1) lecture-only instruction, 2) lecture plus demonstrations, and 3) lecture, demonstrations and vocabulary interventions. A variety of vocabulary interventions were used such as continuous exposure to a word wall and vocabulary-centric assignments including word matching. Student comprehension of plate tectonic phenomena was evaluated both pre- and post-instruction with a concept mapping exercise and a quantitative multiple-choice instrument composed of questions from the Geoscience Concept Inventory (GCI) and the Ohio Graduation Test. Concept maps were scored via established methods as was the multiple-choice test, providing two different measures of quantitative gain. Initial results indicate that students who engaged in vocabulary interventions gained greater understanding of plate tectonics than students who experienced to more traditional lessons. This difference was evident for both the concept mapping and multiple-choice scores. This study suggests that scientific vocabulary may impede learning of basic geoscience concepts unless vocabulary is explicitly targeted during instruction.