Conservation of quantity in preschool and younger school age

The aim of this thesis was to try to repeat the well-known experiment of Jean Piaget, which investigates the process of acquiring the notion of conservation of quantity and hence to reproduce his theory by examining present-day population of children. At the same time we have tried to question the theory and the answers were supposed to create kind of alternative theory and add a few new findings to it. At first we have studied relevant parts of Piaget's monography called The Child's Conception of Number (Piaget, 1997) so that we could understand his conclusions. We adopted his own design of experiment which was then slightly modificated in order to provide a space for our own experimental hypothesis. The experiment was carried out with the help of sixteen children in the age of 4 to 7,5 years. We used qualitative analysis to get our own interpretation of obtained data in the same way Piaget did in the past, except that we have also focused on particular childrens' reactions that led us to the answer to our experimental questions. In the last part of the thesis we have confronted our findings with those of Piaget and thus we have demonstrated a possibility of expanding Piaget's theory as well as taking a different point of view of it. As we could not identify (based on our own analysis) with all of Piaget's..