Extends prior theory and research by postulating the existence of an intermediate class of concepts called 'hypothetical'. Investigates the hypothesis that three kinds of scientific concepts exist by constructing and administering a test on concepts introduced in a college biology course. Supports the hypothesis that intellectual development…

The constructivist hypothesis that the acquisition of domain-specific conceptual knowledge (declarative) requires the use of general procedural knowledge was tested. Students (n=314) were classified as reflective, transitional, or intuitive thinkers and presented with four concept-acquisition tasks. Skill in hypothetico-deductive reasoning…

The reasoning abilities to be expected of the concrete operational and formal operational student, the percentage of secondary science students that are capable of each type of reasoning pattern, and effective strategies to teach science to concrete reasoners are described. Implications for curriculum development are discussed. (KR)

The purpose of this descriptive study was to investigate the developmental patterns in logical reasoning of students in grades 6-10 over a span of 20 months. The Group Assessment of Logical Thinking (GALT) was administered to the sample (N=84) during the fall of 1986, the fall of 1987, and the spring of 1988. The GALT measures six reasoning modes:…