1984'6, p.33
Kechakmadze I. K.
Psychological conditions of development of the idea of invariance of quantity in six-year-old children
(RESUME)

Ability to perform tests on invariance of quantity is considered by some psychologists to be a criterion of the child's readiness for school. The purpose of the author's experiment was to establish the state of the corresponding concept in six- and seven-year-old children and then to study the effect of regular teaching on the ability of six-year-old children to comprehend the invariance of quantity. At the beginning of their school education both groups of children are at the same level, and their mental abilities and intelligence develop at the same rate during the first year as far as comprehension of the invariance of quantity is concerned. However by the end of the first year 50 % of the children who attended the preparatory classes (two years of studying there) successfully performed the test while in those who had not studied in the preparatory class only 35,5 % were successful.