The concept developmentally appropriate has been promoted through policies and publications of the National Association for the Education of Young Children (NAEYC), which has a current membership of 93,000 early childhood educators in child care agencies, public and private schools, and postsecondary educational institutions. NAEYC's position statement on Developmentally Appropriate Practice in Early Childhood Programs Serving Children from Birth Through Age 8 defines developmental appropriateness in terms of two dimensions: age appropriateness and individual appropriateness. Early childhood learning environments and experiences are age appropriate when they are consistent with knowledge of how young children of the particular age span typically develop. They are individually appropriate when they respond to the unique "pattern and timing of growth, as well as individual personality, learning style, and family background" of each child in the group.
The concept of developmental appropriateness is applied to assessment in the following instances:
"In real life, children are most themselves when they are in familiar environments with adults and children whom they know and trust, engaged in tasks that allow them to use the modalities with which they are most comfortable. In such situations they will most likely demonstrate the knowledge, skills, and attitudes that truly represent their attainments. When we introduce strange people, unfamiliar surroundings, demands for responses to atypical tasks, and constrictions on their usual behaviors, we will likely elicit behaviors that are neither valid nor reliable samples of the children's development and learning." (Hills, 1993, p. 22)
"Good schools for young children move away from reliance on standardized achievement tests of basic skills, as well as policies of tracking or retaining children. They move toward a philosophy of assessment that is continuous, based on children's performance, and directed by the teacher." (National Association of State Boards of Education, 1991, p. 35)