# Lesson 2

Chance Experiments

### Lesson Narrative

In this lesson students investigate chance events. They use language like impossible, unlikely, equally likely as not, likely, or certain to describe a likelihood of a chance event. Students engage in MP1 by making sense of situations and sorting them into these categories. In some cases, a value is assigned to the likelihood of an event using a fraction, decimal, or percentage chance. By comparing loose categories early and numerical quantities later, students are attending to precision (MP6) when sorting the scenarios. Later, students will connect this language to more precise numerical values on their own.

### Learning Goals

Teacher Facing

• Comprehend and use the terms “impossible,” “unlikely,” “equally likely as not,” “likely,” and “certain” (in spoken and written language) to describe the likelihood of an event.
• Interpret percentages, fractions, and decimals that represent the likelihood of events.
• Order a given set of events from least likely to most likely, and justify (orally) the reasoning.

### Student Facing

Let’s investigate chance.

### Required Preparation

Print and cut up slips from the Card Sort: Likelihood blackline master. One copy is needed for every 3 students. 2 standard number cubes are needed for a demonstration.

### Student Facing

• I can describe the likelihood of events using the words impossible, unlikely, equally likely as not, likely, or certain.
• I can tell which event is more likely when the chances of different events are expressed as fractions, decimals, or percentages.

### Glossary Entries

• chance experiment

A chance experiment is something you can do over and over again, and you don’t know what will happen each time.

For example, each time you spin the spinner, it could land on red, yellow, blue, or green.

• event

An event is a set of one or more outcomes in a chance experiment. For example, if we roll a number cube, there are six possible outcomes.

Examples of events are “rolling a number less than 3,” “rolling an even number,” or “rolling a 5.”

• outcome

An outcome of a chance experiment is one of the things that can happen when you do the experiment. For example, the possible outcomes of tossing a coin are heads and tails.