Current initiatives in science education in Korea have emphasized science literacy as the most important purpose of science education; that is, science education needs to focus on helping each student to become a scientifically literate person who is able to make reasoned decisions. In attempting to address this focus concern about science literacy, the researchers of this study attempted to implement the Science Writing Heuristic (SWH) approach and examined both the SWH and the control groups using the modified Reformed Teaching Observation Protocol (RTOP). Students' performance on a Summary Writing Test (SWT) was also examined. Participant students of this study were eighth grade students in three middle schools located in the second biggest city in Korea. Each of the three teachers from three schools taught both the SWH and the control classes. The results of this study showed significant differences between the SWH and the control groups on the SWT. There was a difference in the total RTOP scores between the SWH and the control groups. Differences among schools imply that higher level of teachers' implementation of the SWH approach would appear to result in better student achievement.

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The primary objective of this paper is to present the findings of field studies that investigated variations in crack widths over time in three continuously reinforced concrete pavement projects in Texas. Also presented are crack width variations through the slab depth. Vibrating wire gauges were installed at three slab depths—top, middle, and bottom—during concrete placement. Transverse cracks were induced at the locations of the gauges, and concrete strains were measured. The ages of the projects varied from 11 months to 2 years, 10 months. Significant variations existed in crack widths along the slab depth. Crack widths were largest at the top and smallest at the bottom. In the test sections of this study, crack widths at the middepth were about three-quarters of those at the top. Crack widths at the top and middepth were a direct function of temperature variations in the concrete at those depths. However, there was a poor correlation between concrete temperatures and crack widths at the bottom. There was clear evidence that moisture variations in concrete have substantial effects on concrete volume changes and crack widths. An immediate decrease in crack widths was observed after rains. Crack widths decreased over time within the time frame of this study. This finding is not consistent with the current theory on crack width variations over time, and further study is currently under way at the University of Texas at Austin to identify the causes. The findings will be reported as they become available.

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