ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 51, Number 6
JKCSEZ 51(6)
December 20, 2007 

The purpose of this study was to investigate cognitive acceleration effect of the experimental group over
three years compared with the control group through the ‘Thinking Science’ program in the middle school students. The
‘Thinking Science’ program was implemented to 168 students in 7th grade over a period of two years. After implementation
of the ‘Thinking Science’ program, the improvement of formal thinking ability of the students was almost twice examined
with SRT VII as the post-test and the delayed test. It was shown that by the end of the implementation period the experimental
group had achieved a significantly greater gain score in levels of cognitive development than had the control group.
In the subsequent year during which there was no further implementation, the experimental group continued to develop at
the same rate as the control group. However, it is clear that much more experimental students in mature concrete operational
stage shifted to formal operational stage in delayed test. The results were also analyzed by gender, and cognitive levels of
the students. In the post-test, the ratio of girls that shifted to formal operation stage in the experimental group increased as
compared with the ratio of boys, while, in the delayed test cognitive level of boys was more effective than that of girls.