Keele Research Repository

This thesis reports seven experiments on how children, aged 9 to 15 years, deal with problems in which categorizing may be used to impose advantageous order on the problem-solving process. The first three experiments present a total of 108 children with Twenty Questions games. There are significant age-related changes in the types of question asked, notably a change from particular to categorical questions. However, these changes are not accompanied by significant changes in problem-solving efficiency as measured by the number of questions required for solution. It is concluded that the half-split algorithm does not develop spontaneously but in response to special pressures which are investigated in Experiments 4 and 5, making a total of 91 children. Experiments 6 and 7 involving a total of 78 children, uses a recall task to examine the use of categorizing as a means of fascilitating recall. In these problems, older children are found to make more spontaneous use of categorizing, while the recall of younger children is greatly improved when they use prior category cues and are instructed how to use these cues.