Cognitive development refers to the growth in mental activity, capacity, and productivity in all human beings. The paradigm of "scaffolding", as it relates to cognitive development, was proposed in part by Lev Vygotsky. It consists on a variety of teaching strategies used as interventions to introduce new information. As the educator expands the process of teaching, students will make connections among things that they have already learned.
As students make the connections, more information can be given to them, and they will need less aid from the teacher. The goal is for the student to produce something that can be used to demonstrate how much of the new information is actually understood, and how it can be reproduced by the student without the help of the teacher.
However, if we compare the process of scaffolding between an adult and a child, the first thing that would differentiate them the most is the capacity for making connections. Adults possess the schema that enables them to connect topics, understand similarities and differences, and form conclusions.
Children, on the other hand, need concrete, visual, and relevant information in order for them to understand new things. They also need to be continuously exposed to visual, auditive, and kinesthetic learning opportunities so that they can create a foundation of knowledge over which they can begin the process of scaffolding.
In all, we all need schema to connect ourselves to new information. However, between children and adults, the key element is previous knowledge and experiences.