Testing One Premise of Scientific Inquiry in Science Classrooms: Examining Students' Scientific Explanations and Student Learning

In this study. we analyzed the quality of students written scientific explanations found in notebooks and explored the link between the quality of the explanations and students' learning. We propose an approach to systematically analyzing and scoring, the quality of students' explanations based on three components: claim, evidence to support it, and a reasoning that justifies the link between the claim and the evidence. We collected students' science notebooks from eight science inquiry-based middle-school classrooms in five states. All classrooms implemented the same scientific-inquiry based curriculum. The study focuses on one of the implemented investigations and the students' explanations that resulted from it. Nine students' notebooks were selected within each classroom. Therefore, a total or 72 students' notebooks were analyzed and scored using the proposed approach. Quality of students' explanations was linked with students' performance in different types of assessments administered as the end-of-unit test: multiple-choice test, predict-observe-explain, performance assessment, and a short open-ended question. Results indicated that: (a) Students' written explanations can be reliably scored with the proposed approach. (h) Constructing explanations were not widely implemented in the classrooms studied despite its significance in the context of inquiry-based science instruction. (c) Overall, a low percentage of students (18%) provided explanations with the three expected components. The majority of the sample (40%) provided only claims without any supporting data or reasoning. And (d) the magnitude of the correltations between students' quality of explanations and their performance. were :ill positive but varied in magnitude according to the type of assessment. We concluded that engaging students in the construction of high quality explanations may he related to higher levels of student performance. The opportunities to construct explanations in science-inquiry based classrooms, however, seem to be limited. (C) 2010 Wiley Periodicals, Inc J Res Sci Teach 47: 583-608, 2010