Secondary science students were tested, using Piagetian tasks to determine their level of intellectual development, and then tested on scientific concepts classified as concrete or formal. Results showed significant multiple correlations between the scores on the tasks and the subject matter tests. (MLH)

Effects of external reinforcement and cognitive conflict-based treatments on students' acquisition of ability to control variables at an early age were studied. Smedslund's finding was confirmed. Nearly half of trained students with a mean age of 11.8 years could be classified in late formal operations. (CC)

Analyzes the performance of the Electronic Task (ET), to test for combinatorial reasoning, over a broad range of subject ages and abilities in order to evaluate it as a substitute for the original Chemical Task (CT). (GA)