Teach students the definition of probability -- the chance the something will happen. Offer them the following equation to determine probability: Probability is equal to the number of ways something can occur over the total number of possible outcomes.
Illustrate the given equation using a coin. Since there are two sides to a coin, there is one chance out of two that the coin will land on heads or that the coin will land on tails, making the probability of landing on either heads or tails one out of two.
Give the children a die. Instruct them to count the total amount of numbers illustrated on it. Since you will be using a six-sided die, the total amount of numbers illustrated equals six. Explain to students that six is the number that goes on the bottom of the equation; the probability of rolling any number on the die will be out of six.
Explain to students that because there are six individual numbers on the die, the possible outcome of rolling any of the numbers is one; so one would be the number that goes on the top of the given equation. For example, there is a one-out-of-six chance that the die will land on one when it is rolled, there is a one-out-of-six chance that the die will land on two when it is rolled, and so forth for each number on the die.
Have students try to determine the probability of rolling an even or odd number once they understand the probability of rolling any of the individual numbers. Instruct students to count the total number of even and odd numbers on the die -- three in both cases.
Explain to students that the number three will be the number that goes on the top of the given equation, since there are three even and three odd numbers. Explain to them that since there are still six total numbers on the die, six still represents the bottom number in the given equation. Therefore, in the case of rolling an even or odd number, the probability is three out of six.