The Open Field Test was used to assess variables that might not be manifested in a more standard testing situation. In this test, the child was shown 10 standard play objects in the room, and was told to do anything he wished with the toys. The tester initiated no interaction with the child and responded minimally to any overture made by the child. During each 30-second period of the 10-minute test, the tester recorded and described every play activity involving each object, along with a variety of nonplay activities. Following a process of score reduction, four scores were used in structural analyses: mean complexity of play, number of periods child talked to tester, number of periods child talked to self, and number of simple sequences. For each of these scores, age x sex x SES repeated measures measures analysis of variance was performed. For mean complexity of play, a significant effect of sex was present; males tended to engage in more complex play. There were no effects attributable to age or SES. In the analyses for the number of periods in which the child talked to the tester, a marginal effect of SES and a marginal year by SES interaction was shown; age and sex had no significant effects. Number of periods child talked to self showed a significant effect in the Year 1 data only, with males engaging in more talk. In number of simple sequences, Year 1 data showed a marginally significant SES effect. Results suggest negative evidence that what was measured was different. Eight tables provide the study data. In addition, the Coding Manual and Answer Sheet are included. (For related documents, see TM 003 174-187, 189-198.) (DB)