Materials Conceptions.pdf

Students' conceptions of the structure of materials in Junior High School were investigated through a longitudinal study and the development of new learning materials and instructional methods. 1300 students from experimental and comparison groups represented the structure of materials verbally and visually in questionnaires administered five times during a 3-year period, with 85% of the experimental group reaching a microscopic model and 36% reaching a molecular model. A new interdisciplinary learning unit, "About Fibers," was developed and implemented, using the Science-Technology-Society approach and emphasizing the macro/micro view of materials. The results showed significant improvement in students' descriptions of the particulate model and molecular structure of materials. The study also explored the use of the Scanning Tunneling Microscope as a learning tool, which contributed to students' understanding of the particulate nature of matter. The evidence suggests that the particulate nature of matter can be learned with appropriate curricula and teaching methods, and recommends including components such as a constructivist approach, spiral teaching, macro/micro views, knowledge-integration activities, and new instructional methods like STS and high-resolution microscopy.