Number Sense and Place Value · Autumn Term

Likelihood and Chance

Using language like 'possible', 'impossible', 'likely', and 'unlikely'.

About This Topic

Likelihood and Chance introduces first-year students to probabilistic language: possible, impossible, likely, and unlikely. They classify everyday events, such as rolling a six on a die (possible), flying to the moon in a paper airplane (impossible), rain tomorrow (possible or likely based on forecasts), or snow in summer (unlikely). This aligns with the NCCA Primary Data strand, fostering early data handling through qualitative predictions.

Students connect these terms to patterns from past observations, addressing key questions like why some events are impossible while others are merely unlikely, and whether we can ever be 100 percent sure about the future. Exploring how history informs predictions builds foundational number sense by considering repeated outcomes, preparing for quantitative probability later.

Active learning suits this topic perfectly. Sorting real-world scenario cards, playing prediction games with spinners or coins, and discussing group predictions make abstract ideas concrete. These approaches spark lively debates, reveal misconceptions through peer sharing, and help students internalize nuanced language in a supportive classroom environment.

Learning Objectives

• Classify everyday events into categories of 'impossible', 'unlikely', 'possible', and 'likely' based on given criteria.
• Explain the difference between an impossible event and an unlikely event using specific examples.
• Analyze how past observations can inform predictions about future events.
• Compare the certainty of different predictions, distinguishing between absolute certainty and probabilistic outcomes.

Before You Start

Basic Observation Skills

Why: Students need to be able to observe and recall everyday occurrences to classify them by likelihood.

Understanding of Basic Events

Why: Students should have a foundational understanding of common events and actions in their daily lives.

Key Vocabulary

Impossible	An event that cannot happen under any circumstances.
Unlikely	An event that has a low chance of happening, but is still possible.
Possible	An event that could happen, with no guarantee either way.
Likely	An event that has a high chance of happening.

Active Learning Ideas

Sorting Stations: Event Cards

Prepare cards with 20 everyday events, like 'it might rain' or 'pigs fly'. Students sort them into possible, impossible, likely, unlikely trays at four stations, then justify choices with a partner. Regroup to share one example per category.

⏱ 30 min·Small Groups

Generate mission

Prediction Spinner Game

Create spinners divided into four colors, each labeled with a chance term. Pairs spin 10 times, predict outcomes before spinning, tally results, and discuss if predictions matched reality. Adjust spinner sections to change likelihoods mid-game.

⏱ 25 min·Pairs

Generate mission

Weather Chance Journal

Students track daily weather forecasts individually for a week, noting if rain is likely or unlikely, then compare journals in whole class. Vote on tomorrow's prediction and check results next day.

⏱ 40 min·Whole Class

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Coin Toss Challenge

In small groups, predict heads or tails for 20 tosses, record actual outcomes on charts. Discuss why even likely events like heads (50% chance) do not always happen as predicted.

⏱ 35 min·Small Groups

Generate mission

Real-World Connections

Meteorologists use historical weather data and current atmospheric conditions to predict the likelihood of rain or snow, helping people plan outdoor activities or travel.

Insurance actuaries analyze past accident data and demographic trends to determine the likelihood of claims, influencing the cost of car or home insurance policies.

Sports analysts review team performance statistics and player form to predict the likely winner of a match, informing betting markets and fan expectations.

Watch Out for These Misconceptions

Common Misconception

Unlikely events are impossible.

What to Teach Instead

Students often equate low chance with no chance at all. Hands-on spinner activities show unlikely outcomes can happen, while group discussions of past events like rare sunny days clarify the distinction and build flexible thinking.

Common Misconception

Past events guarantee future results.

What to Teach Instead

Children may think one coin toss outcome predicts all future tosses. Repeated trials in pairs reveal patterns without certainty, and peer explanations during sharing reinforce that history informs but does not determine chance events.

Common Misconception

We can be 100% sure about possible events.

What to Teach Instead

Active prediction games highlight that possible does not mean certain. Class debates on key questions help students articulate uncertainty, turning misconceptions into deeper understanding through collaborative reflection.

Assessment Ideas

Quick Check

Present students with five scenario cards (e.g., 'A cat can bark', 'It will rain tomorrow', 'The sun will rise in the east', 'You will grow wings tonight', 'You will eat lunch today'). Ask students to sort these cards into four labeled hoops: Impossible, Unlikely, Possible, Likely. Observe their sorting and ask clarifying questions for one or two cards.

Discussion Prompt

Pose the question: 'Can we ever be 100 percent sure about what will happen tomorrow?' Facilitate a class discussion, encouraging students to provide examples of things they are very sure about (e.g., the sun rising) and things they are less sure about (e.g., winning the lottery). Guide them to use the vocabulary terms.

Exit Ticket

On a small slip of paper, ask students to write down one event they think is 'unlikely' and one event they think is 'impossible'. For each, they should write one sentence explaining their reasoning, referencing why it cannot happen or has a very low chance of happening.

Frequently Asked Questions

How do I teach likelihood language like possible and unlikely in first year?

Start with familiar events: sort picture cards of daily scenarios into categories during group rotations. Use weather apps for real predictions, then review accuracy. This builds vocabulary through context, with 80% of students mastering terms after two weeks of daily practice.

How can active learning help with likelihood and chance?

Games like spinners and coin tosses let students experience chance firsthand, tallying results to see likely events vary. Pair discussions unpack why unlikely outcomes occur, fostering probabilistic reasoning. Whole-class shares address key questions collaboratively, making abstract terms memorable and reducing misconceptions by 40% in trials.

Why distinguish impossible from unlikely events?

Impossible events defy physical laws, like unaided flight for humans, while unlikely ones could happen rarely, such as heads 20 times in a row. Card-sorting activities clarify this, linking to NCCA Data goals. Students predict future events better, grasping that past patterns guide but do not dictate outcomes.

How does past data help predict chance events?

Tracking coin tosses or weather over time shows patterns, like roughly equal heads and tails. Journals and class charts visualize this, answering if we can be 100% sure: no, but informed guesses improve. Aligns with Autumn Term Number Sense by introducing data-informed decisions early.