The Sigel Object Categorization Test (SOCT) is used for studying classification abilities in young children, the criteria for which is considered indicative of both cognitive ability and style. The test consists of two types of stijuli--one set of 12 relatively familiar three-dimensional objects and a second set of colored photographs of these objects. An active or passive sort can be used. Year 1 and Year 2 testing used objects and the active sorting condition. After the child identifies each object, E selects a different object on each of 12 trials and asks the child to put it with the ones that are the same. Three trials, with differently worded instructions, are possible for each item. After the child has selected objects to go with the stimulus, E asks for the rationale for the sort. Latency to first object choice is also recorded. Responses are scored on the basis of verbal level and type of classification. The low mean scores for total grouping responses indicate the task was fairly difficult for this age group. Response stability across years was low. An increase in grouping responses in the Year 2 data was observed. Within-year age differences were evident in both years. Most Ss were able to recognize and correctly lable most of the objects, but few were able to give reasons for their groupings. Significant SES differences were also found. The SOCT provides a wealth of data, but it is difficult to use in large-scale evaluations, and administration and scoring require a great deal of training. (For related documents, see TM 003 174-194, 196-198,) (KM)