Explain that there are different ways of learning things. Ask the children how they know that Africa exists. Most, if not all, have probably never been to Africa, but they know it exists because someone has told them about it, or because they have seen pictures or movies about it. Tell them that hearing about something, or seeing pictures of it, is one way of knowing. A second way of knowing is by thinking and figuring things out through reason and observation. This is called logic.
Teach your students about inductive logic, which is based on observation. Show them many pictures of an animal, such as a dog or a penguin. Ask them to look at all the pictures and then tell you what features they think are common to all dogs, or all penguins. They might conclude, for example, that while dogs have different colored hair, all dogs have hair, or that all penguins have two feet. Explain to them that now, by observing and thinking, they know something that applies to all, or almost all, penguins or dogs. They don't need to see every single penguin to know that penguins have two feet; they can generalize based on the pictures they have seen.
Explain deductive logic, which is based on reasoning. Deductive reasoning starts with a general statement that is true, then reaches a secondary statement that depends on the first. Ask your children to give examples of facts they have learned in science class or social studies. If they tell you, for example, that all mammals are warm blooded, explain that they can now know whether a specific animal is warm blooded by determining whether it is a mammal. Ask for an example of a mammal. Write a deductive syllogism based on the example they give, showing the sequence of logical thought. Using a rabbit as the example of a mammal, you would write: "All mammals are warm blooded. Rabbits are mammals. Therefore, rabbits are warm blooded."