Discussed in this report is a technique used in cross-cultural research for measuring cognitive processes in children and youth. The research strategy aims at evaluating the subject's performances on problem solving tasks by having subjects become active agents in the discovery process while experimenters remain as passive and neutral as possible. The subject is asked to solve a problem by asking questions to get the information he or she needs to reach a solution. The subject becomes an active searcher; the experimenter only provides the information requested. The subject's tactics indicate how he or she deals with the structure of the problem. Thinking about a problem becomes a way of making explicit and communicable to oneself or to others its logical structure. If this is so, it is of interest to know how subjects belonging to different cultural settings process problems, and the influence that their structure and the symbolic system used (manner of presentation) have on tactics. The subject's performance can then by analyzed in terms of the set of logical rules that he or she uses and of the symbolic systems that favor or hamper problem solving performance. (CS)