# Basic Probability Background Information for Teachers, Parents and Caregivers

This page provides information to support educators and families in teaching K-3 students about basic probability. It is designed to complement the Basic Probability topic page on BrainPOP Jr.

Review with your children that when they predict, they use what they know to think about what might happen. They rely on clues and prior knowledge to make an educated guess. Probability is the chance or possibility that an event will happen. Explain that they can decide what will or will not happen, or and make choices about what is likely or unlikely to occur. This movie will explore common terms associated with probability, including *certain, impossible, possible, likely, unlikely, more likely, less likely,* and *equally likely.* We recommend brainstorming various likely or unlikely events together and having students use different vocabulary words in complete sentences to help reinforce the new words. We also recommend using plenty of hands-on activities with manipulatives such as counters, marbles, coins, and spinners to help reinforce the lessons.

Remind your children that if something is certain, it will definitely happen. Have your children brainstorm different events that are certain. For example, the Sun will rise and set everyday, and people will breathe air. If something is impossible, it means it will not happen. Ask your children to think of impossible events. Ideas might include growing wings, going to the Sun, or breathing underwater. Why are these events impossible? If something is possible, it means it could happen. Have them brainstorm possible events, such as visiting another country or getting a new puppy. It is important for children to understand that possible events may or may not actually happen, but they can happen.

If something is likely, it means that it will probably happen. Have children describe a likely event. For example, it is likely they will read from a book next week. Encourage them to use complete sentences using the word *likely*. Explain that if something is unlikely, it means that it will probably not happen. Have children describe an unlikely event, such as getting a pet pig. Be sure to point out that unlikely events are not impossible events. Some people do have pet pigs, but it is uncommon.

Have children compare the likelihood of different events using the phrases *more likely* or *less likely*. For example, it is more likely that they will play soccer at recess than go swimming at the beach. It is less likely that they will leave school early to go to an amusement park. Show a clear bag of two different colors of counters, such as blue and red connecting cubes. Make sure there are more blue cubes than red. If they chose one cube from the bag, what color would it be? Since there are more blue cubes than red, it is more likely they would pick a blue cube. It is less likely they would pick a red cube. Repeat the activity again except have equal numbers of red and blue cubes. Since there are equal numbers of red and blue cubes, it is equally likely to pick a red or a blue cube. You may wish to repeat the activity again using different colors of counters or making your own spinners.

Explain to your children that since a coin has two even sides, it is equally likely for it to land on heads or tails. Take turns tossing the coin and keeping track of the way it lands by using a tally chart or bar graph. Stop the activity after ten tosses and assess the results. Then continue the activity again for twenty or more times and see how the results change. Explain that when they are testing their predictions, they should do the experiment multiple times because the results can change over a long period of time.

Hold a discussion with your children about how they make predictions everyday. How are predictions useful? How might people be able to forecast the weather? What clues do they use to make their predictions? Give children an opportunity to make a prediction and test it.