Provides examples of if-then and combinatorial reasoning situations that have proved successful with college students and can be used with secondary school students. Proposes that practice with these problem solving processes can eliminate the need to memorize formulas that students may not understand. (ML)

Describes a science experiment that gives students experiences with the float-sink phenomena and allows them to practice what Piaget called formal operational thinking. The goal of the experiment is to determine some of the variables responsible for cans of soda sinking or floating. (TJQ)

Defines the mathematical concept of proportionality. Uses graphs of linear relationships to explore and make generalizations about the characteristics of proportional situations to help students critically evaluate problems involving proportions. (MDH)

Attempts to show that not only can density be taught to lower ability pupils but that by doing so, there is the possibility of assisting pupils to develop their reasoning powers. Lists teaching activities that help in this process. (CW)

Physical and Earth Science AB, a required senior high school course in the Los Angeles Unified School District, uses an investigative approach for developing scientific understanding and attitudes for students. Contents include: (1) summary of representative objectives; (2) teacher responsibilities; (3) the agenda; (4) guidelines for assignment of…