Maths topic
Chance and probability
What children learn in chance and probability, from their first year of school to the end of primary, and the lessons to watch together.
What's taught, year by year
The steps in chance and probability, in the order children usually meet them. Years are named as in Australia; the ages are a guide.
Year 1 ages 6–7
- Will happen, might happen, won't happen. Sort everyday events by whether they will happen, might happen or cannot happen.
Year 2 ages 7–8
- Certain, likely, unlikely, impossible. Describe how likely everyday events are using chance words and give a reason.
Year 3 ages 8–9
- Do a chance experiment and record the results. Flip, roll or spin many times, tally the outcomes and notice that results vary each time.
- Order events from least likely to most likely. Put a set of events in order of how likely they are and justify the order.
Year 4 ages 9–10
- Does the last result change the next? (independent events). Decide whether one outcome affects the chance of the next, such as coin flips versus taking sweets from a bag.
- List all the possible outcomes. Write down every outcome of a coin, die or spinner (the sample space).
- Equally likely or not? Fair and unfair spinners. Decide whether outcomes are equally likely by looking at a spinner, die or bag and say if a game is fair.
- Place events on a 0 to 1 likelihood line. Mark events on a line from impossible (0) through even chance (1/2) to certain (1).
Year 5 ages 10–11
- Use results from many trials to estimate chance. Use the frequency of each outcome over repeated trials to estimate and compare how likely outcomes are.
- Write a probability as a fraction. Write the chance of an outcome as favourable outcomes over all equally likely outcomes.
- Outcomes of two events together (coin and die). List the combined outcomes of two events in a table or tree and find the chance of one combination.
- Events that cannot happen together. Recognise when two outcomes cannot both happen on one trial, such as rolling a 2 and rolling an odd number.
Year 6 ages 11–12
- Probability as a fraction, decimal or percentage. Convert a probability between fraction, decimal and percentage forms on a 0-1 or 0-100% scale.
- Expected versus actual results: why more trials help. Compare what should happen with what did happen and see results settle down as trials increase.
- The chance of something not happening. Find the probability that an event does not happen by subtracting its probability from 1.