The issue of how adults help children to perform and learn has received a great deal of recent attention. Much of this research stems from the sociohistorical ideas of the late Russian psychologist L. S. Vygotsky (1978, 1934/1986, 1987), especially his conception of the zone of proximal development (zpd). In essence, the zpd represents the child's susceptibility to influence, that is, the difference between what a child can do with assistance and what he or she is able to do without it. It is assumed that most capable adults are able to target appropriately their strategic interactions with children within the latter's zpd, thereby facilitating learning. However, the actual empirical evidence for the relationship between strategic assistance (or scaffolding) and learning is currently somewhat limited and not altogether telling (Levine, Schneider, Pelland, & Hall, 1987).

There are two major problems for those who would interpret the findings from mother–child studies. The first is that there is little consensus about what to look for in the mother–child dyad that would constitute evidence for scaffolding. That is, theory would dictate that some aspect of the joint doing of a task, or verbal (and nonverbal) interaction about and for it, would be what is internalized by the child. The most immediate, and visible, expression of effective scaffolding would be the child's improved performance on the task at hand and/or on a near-transfer task. However, beyond these generalities there is nothing inherent to the theory that would predict just what about the doing of the task, or the talking about it, would lead to learning.