Outcomes and Events

Overview

This lesson develops pupils’ understanding of sample spaces, outcomes and events, using simple probability experiments such as coin tosses and dice throws. It builds toward later lessons on calculating probabilities by first ensuring pupils can clearly list possible outcomes and identify events.

Learning intentions

Students will:

• Define what an outcome is in a probability experiment.
• Generate a sample space for equally likely results.
• Identify events as sets of outcomes, using correct probability language (e.g., “event”, “outcome”, “sample space”).
• Explain their reasoning using tables, lists, and simple representations.

Success criteria

Students can:

• List all outcomes for a given experiment without missing any.
• Write a clear sample space in a consistent format.
• Identify an event and list the outcomes that belong to it.
• Explain how their event relates to the experiment.

Curriculum links

• Record, describe and analyse the frequency of outcomes using appropriate probability language and a 0–1 probability scale (foundation for later probability calculations).
• Generate theoretical sample spaces for single and combined events with equally likely, mutually exclusive outcomes and use these to calculate theoretical probabilities (sample spaces and events today).
• Understand that the probabilities of all possible outcomes sum to 1 (introduced through “all outcomes” meaning nothing is left out).

Lesson structure (60 minutes)

1. 0–5 min · Do Now. Teacher displays a simple prompt: “Toss a coin. List possible outcomes.” Students face front, silent, arms crossed, then draw and list outcomes (heads/tails) in books.

2. 5–10 min · Do Now share + quick check. Teacher asks two pupils to share answers; teacher stresses “all possible outcomes” and corrects missing/incorrect lists. Students turn and talk for 1 minute: “What would happen if you forgot one outcome?” Then pupils update their lists.

3. 10–22 min · I Do (teacher modelling). Teacher models sample spaces using a coin toss and a single die:

• Coin toss: outcomes {H, T}. Sample space is the complete set of outcomes.
• Dice throw: outcomes {1,2,3,4,5,6}. Teacher then introduces an event: “Event A: roll an even number.” Event outcomes are {2,4,6}. Students copy a short example table/list from the board, using the sentence: “The sample space is… The event is… The outcomes in the event are…”

4. 22–35 min · We Do (guided group creation). Teacher groups pupils (pairs or threes) and gives scenario cards. Examples (choose 4 across the group):

• “Spin a spinner with 4 equal sections: Red, Blue, Green, Yellow.” Ask for sample space.
• “Throw a die. Event B: roll a number greater than 4.” Ask for the event outcomes.
• “Coin toss and die together.” Ask for a combined sample space format (outcomes written as pairs, e.g., (H,1)). Teacher circulates and checks lists are complete and events are correct subsets. Students work, then each group completes one “teacher check” answer on mini-whiteboards.

5. 35–42 min · Whole-class check (micro-feedback). Teacher selects one strong and one flawed solution and prompts: “Is it a complete sample space? Is the event a subset? What is missing or incorrect?” Students face front and silently revise one key point in their books.

6. 42–55 min · You Do (worksheet). Teacher distributes the worksheet:

• Part A: “For each experiment, list the sample space.” (coin/number wheel/die outcome lists)
• Part B: “For each event, write the outcomes in the event.” (e.g., “roll a multiple of 3”, “coin is tails”, “spinner shows either Red or Blue”)
• Part C: “Match event name to listed outcomes” (short reasoning). Students work independently; teacher targets misconceptions: incomplete sample spaces and mixing up “event” with “outcome”.

7. 55–60 min · Exit check + closure. Teacher reads two quick statements; pupils answer on mini-whiteboards:

• “Sample space for a die is {1,2,3,4,6}.” True/False (and why).
• “Event: roll an odd number.” Which outcomes belong? Teacher closes by reminding: events are sets of outcomes inside the sample space.

Resources

• Coin and die visuals (real or projected)
• Scenario cards for We Do (spinner/coin/die)
• Mini-whiteboards and pens
• Worksheet: sample space and event identification
• Timer for turn-and-talk segments
• Dyslexia-friendly reading version of the worksheet (short sentences, larger font, clear headings)
• Sentence starters on a prompt sheet (for pupils who need support): “The sample space is…”, “The event is…”, “The outcomes are…”

Assessment

• Formative: Observe Do Now lists and We Do mini-whiteboards for completeness and correct use of “sample space” vs “event.”
• Formative: During You Do, check pupils can correctly list outcomes belonging to an event (subset reasoning).
• Exit ticket: True/False for sample space completeness plus event-outcome listing.

Differentiation

• Support:
• Provide dyslexia-friendly text (reduced clutter, larger font) and a worked example on the first page.
• Use sentence starters and a checklist: “Have I listed all outcomes?” “Does my event contain only outcomes from the sample space?”
• For some pupils, allow output as a table (Outcome / Included?).
• On-task scaffold:
• Teacher models consistent ordering (e.g., numbers from 1 to 6; letters in a fixed order H then T).
• Offer a “common mistake” reminder: event outcomes must be taken from the sample space.
• Challenge/extension (advanced learners):
• Combined events: “Coin toss and die together—write the sample space using pairs.” Then: “Event C: tails and a number less than 3.” Ask for event outcomes in pair form.
• Ask them to justify: “How do you know you have not missed any outcomes?”
• EAL/SEN considerations:
• Pre-teach “outcome” and “event” with examples and visual cues (outcomes are individual results; event is a chosen group of results).
• Allow verbal answers during turn-and-talk before written responses.

Success criteria for this lesson (teacher-visible)

• Outcomes listed are complete and correct.
• Sample space is the full set of outcomes for the experiment.
• Events are identified as subsets of the sample space.
• Pupils can state outcomes in the event accurately, using correct probability language.