closed materials can only be used in one way to come out right. puzales and various Montessori materials are closed (vce Figure i). Although such materials are useful in building a sense of competence, they may also become boring once mastered or be frustrating if children are unable yet to master them Program styles that utilize mostly teacher-directed group and individual activities are called closed, as are experiences that have a clear ending Although there are advantages lo both open and closed materials and experiences Prescott (98 l) believes open materials and experiences are especially important for preschool children o experience success and a sense of initiative.