Lead
"I understand!" — followed immediately by doing something completely different. "I can do it," said with total conviction, then abandoned seconds later. "I know that one," and then silence when you ask for an explanation.
If you spend time with four- to six-year-olds, these moments accumulate. It is tempting to interpret them as small deceptions, or as overconfidence. But there is a more useful frame: the ability to accurately monitor one's own understanding — what researchers call metacognition — is still being built at this age. The gap between "I know it" and actually knowing it is not a character flaw in a five-year-old. It is a developmental fact.