A grade placement for which a child is of the right chronological age but too low a developmental age. Some experts in child development believe that over-placement is a major cause of failure at school, and as a result some parents have held their children back to have them be the oldest, and presumably, therefore, the most developed, in the class. This can boomerang, however, as the child grows older, especially during adolescence, and is more mature than the rest of the class, perhaps becoming bored in class as well as restless and socially isolated.