Abstract: 72 three- to five-year-old children were asked about their knowledge states at various points during two types of learning tasks. One was a declarative knowledge task about the contents of a set of drawers and the other was a procedural knowledge task about how to perform simple tricks. In both tasks, subjects were exposed to the knowledge in one of two ways – by seeing and being told about it. Their understanding of “knowing that” and “knowing how” before and after being exposed to the new knowledge, as well as identifying how they learned the knowledge, were the focus of investigation. Before accessing the new knowledge, some subjects in each age group (3-, 4-, and 5-year-olds) reported they “know” when they did not know at all. After exposure to the knowledge, children’s understanding of “knowing that” was better than “knowing how.” For identifying sources, 3-year-olds had great difficulty, whereas older children performed much better, with children in all age groups identifying the sources by which they were exposed to the declarative knowledge tasks better than those for the procedural knowledge tasks.

Key words: knowing that, knowing how, theory of mind, declarative knowledge, procedural knowledge