Teachers lack effective curriculum-based instruments to assess their students' scientific competence that would provide information for modifying their inquiry instruction. The main purpose of this study was to develop and validate a Curriculum-Based Scientific Competence (CBSC) test to assess students' scientific competence in a 1-semester Grade…

The so-called control-of-variables strategy (CVS) incorporates the important scientific reasoning skills of designing controlled experiments and interpreting experimental outcomes. As CVS is a prominent component of science standards appropriate assessment instruments are required to measure these scientific reasoning skills and to evaluate the…

The nature and behavior of gas particles are essential concepts in teaching and learning of school chemistry. However, findings about students' understanding of gas particles--their composition, structure, and interactions involving movement and distribution--revealed that the difficulties students encounter in understanding gas particles vary…

This paper reports on an investigation on the use of an analogy activity and seeks to provide evidence of whether the activity enables students to change alternative conceptions towards views more in accord with scientific views for aspects of solution chemistry. We were also interested in how robust any change was and whether these changes in…

A study of the effectiveness of teaching science to 2 classes of 15 and 20 ninth-graders, respectively, illustrates 5 aspects of educational evaluation: age factors in teachability, test unidimensionality, comparison of 2 classes of students regarding mean ability, objective difficulty of test items, and objective ability of individual students.…