This preliminary study aimed to develop measures that could be used to differentiate kindergartens employing developmentally appropriate and inappropriate instructional practices, and explore the relationship between appropriate and inappropriate practices and stress behaviors of 37 kindergarten children. Four instruments were used to gather data: (1) a Teacher Beliefs Scale; (2) an Instructional Activities Scale; (3) a Checklist for Rating Developmentally Appropriate Practice in Kindergarten Classrooms; and (4) a Classroom Child Stress Behavior Instrument. The measures used were effective in identifying appropriate and inappropriate classes and measuring stress behaviors. With regard to the more substantive findings, results indicated that children in the developmentally inappropriate class exhibited significantly more stress behaviors than did children in the developmentally appropriate class. They also displayed higher frequencies of stress behaviors during whole group and workbook and worksheet activities. Children in the developmentally appropriate class had higher levels of stress during center time and transition activities, but spent much more time in center and transition activities than did children in the other class. Gender differences were also noted. (RH)