The objectives of this module on making comparisons and ratios include using ratios to compare sets of objects and expressing ratios as decimals or fractions in lowest terms. The module provides six experiments. An envelope of manipulatives accompanies each of the first three experiments. The fourth experiment requires a multispeed bicycle. The…

This study investigated several aspects of a teaching experiment which focused on five seventh grade students' performance on nonroutine number theory problem-solving with a close look at the role of heuristics, concrete models, and the relationships between these variables. In the experiment, students were given a series of lessons on number…