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In a large introductory physics course, structured weekly journals (weekly reports) regularly encouraged students to ask questions about the material. The resulting questions were collected for one quarter and coded based on difficulty and topic. Students also took several conceptual tests during the quarter. The reports contained more questions than typically observed in a college classroom, but the number of questions asked was not correlated to any measure of conceptual performance. Relationships among different types of questions and performance on these tests were explored. Deeper‐level questions that focus on concepts, coherence of knowledge, and limitations were related to the variance in student conceptual achievement. © 2003 Wiley Periodicals, Inc. J Res Sci Teach 40: 776–791, 2003

Cultivated land is crucial to food security, social and economic stability, environmental quality, and sustainable urban–rural development in China and around the world. However, most of the current grading systems for evaluating cultivated land quality in China tend to generate homogeneous results and inadequate spatial descriptions mainly due to the use of a composite index method that often fails to recognize the matching relationship between land use needs and the quality of cultivated land. The purpose of this study is to propose a new grading system for evaluating China's cultivated land quality that involves two index systems and a scoring and grading scheme. In the proposed system, cultivated land quality is redefined in terms of production capacity quality and environmental quality, and the minimum limiting factor method and the weighted linear model are coupled for factor scoring and grading. The new system is demonstrated by a case‐study in Yimen Town, a loess plateau region in western China's Shaanxi Province. The results of this study clearly indicate that the new grading system is superior to the current system when compared using two methods: the spatial pattern comparison method and the crop performance validation method. The results are also favorable in terms of matching relationships between the subclasses of cultivated land quality versus soil types and landforms. The new grading system not only helps to better understand the cultivated land quality but also provides a clear direction for science‐based remediation and amelioration of cultivated land.