Two iterative, after school design experiments with small groups of middle students were conducted to investigate how constructed quantitative unknowns, conceived as values fixed quantities that are not known but can be determined. Students solved problems about an unknown height or length measured in two different units. Of 13 who participated, 6 structured into three levels These a consisting...

The transition from middle school to high school is an important developmental period to investigate because of the negative impact it has on youths' academics. The purpose of this study was to investigate Latino youths' academic achievement prior to, during, and after the transition to high school, and gender differences in youths' achievement over time. School transcripts were obtained for 92...