Final answer:
Assimilation is the process by which children integrate new information into their existing mental models or schemata without changing the existing structures. It's part of Piaget's cognitive development theory and is fundamental to how children understand and learn about the world.
Step-by-step explanation:
The concept being described is assimilation, which is when a child uses their existing way of understanding the world to make sense out of new knowledge. This is a key component of cognitive development theory, as proposed by Jean Piaget. Assimilation involves incorporating new experiences into existing schemata (mental models), without changing the schemata. This is distinct from accommodation, where the schemata themselves are altered to fit new information. As children grow and learn, they continuously assimilate and accommodate, allowing them to develop a nuanced and complex understanding of the world around them.