What we know about our world helps us learn more information.
Children sometimes make assumptions about the world that keep them from understanding new information. They might think plants and trees aren't alive because they don't move like humans and animals do or their teachers live at school.
This is why it can be helpful to find out what children already know—or what they think they know—before introducing new material. You'll be able to correct wrong assumptions (but not before writing them down in their baby books). With the correct information in place, they can continue to build on their knowledge of the topic.