A study was undertaken in order to examine (1) the nature of the representation or prototypes underlying children's make-believe object uses, (2) the types of mental activities through which objects are allowed to substitute for real objects, and (3) the awareness children have of processes involved in their choosing and pretending. A total of 18 boys and 12 girls enrolled in two preschool programs participated. Ranging in age from 3 years 11 months to 5 years 5 months, children were divided into two groups matched for age, sex, and preschool program. In a laboratory setting, an experimenter individually invited each child to join her in playing a game. Following a brief introductory period, the experimenter began one of two "scripts" randomly assigned to the subject. Basically, the scripts established a game of pretend including an action requiring a particular implement (e.g., eating ice cream with a spoon). The play setting provided objects that were primary candidates for fulfilling the function of the needed implement as well as "distractors." Results indicated that children made accommodations to the demand characteristics of a systematically varied fantasy context and focused primarily on the criterion of function in selecting objects. Spontaneous talk revealed children's reflectiveness in considering object suitability and their awareness of their own processes of evaluation and pretending. (Author/RH)