Abstract

The purposes of this study were (1) to investigate the differences in children's knowledge of and reasoning about the free-fall phenomenon according to their ages and tasks, and (2) to investigate whether the children's prior knowledge changes to post knowledge through reasoning. Forty from each of three age groups-4-, 6-, and 8-year-olds, for a (total of 120 subjects)were selected for the study. The subjects were chosen from three preschools and two elementary schools located in the middle class residential areas of Seoul and of Kyoung-Ki Province. Each child was to perform tasks dealing with weight and size. Under observation were each child's prior knowledge, reasoning and post knowledge of the free-fall phenomenon. The major findings are as follows: first, there were no differences in the children's prior knowledge of the free-fall phenomenon according to the different age groups. However the prior knowledge level of the size task was higher than for the weight task. There was an interaction effect between ages and tasks. Second, 6-and 8-year old children showed higher levels of reasoning than did 4-year old children. However, there were no differences in the children's reasoning between the different tasks. Third, 6-and 8-year old children showed higher levels of the post knowledge than 4-year old children. However, there was no difference in children's post knowledge according to different tasks. Fourth, there was a significant difference between the prior and the post knowledge. Through measuring the reasonings in the two task experiments, changes in the prior knowledge of the free-fall phenomenon were observed among all three age groups. The difference between prior and post knowledge was higher in the weight than in the size task.