Substrand	Chance
Purpose	Describing possibilities Organising data Reasoning
CSF level suggested	1–2
Equipment	Transparent jar of jelly beans with many of one colour and only a few of any other colours (eg. 30 green, 3 red, 3 black, 3 yellow, 3 pink)

The Task

Students were shown a transparent jar of jelly beans with many of one colour and only a few of any other colours. They were first asked to estimate and record how many of each coloured jelly bean was in the jar. They were then asked to draw and write about what might happen if they shut their eyes and picked out four jellybeans: on Monday, then on Tuesday, then on Wednesday. Students were then asked to explain why they would have picked out those colours.

Look For

• reasonable predictions based on possible outcomes
• recognition that there may be different outcomes for each day
• recognition of a greater likelihood of one colour being drawn
• use of the language of chance

Sally (Year Prep) made unlikely estimates of the numbers of colours. She then predicted four different colours for each day. Some of the colours she chose were not in the jar. "These are my favourite colours." Suggests Level 1 in the substrand.

Sacha (Year Prep) made fair estimates of the relative numbers of colours. She predicted different colour combinations based on the available colours from the jar. She realised you could get two of one colour within the four jellybeans "You might get two the same colour, it depends where you pick them from." Suggests Level 2 in the substrand.

Eliza (Year 1) made reasonable estimates of the relative numbers of colours. She predicted appropriate colour combinations each day, and showed a greater incidence of green jelly beans. Her choices showed ratios of up to 3 green jellybeans to one other colour. "There's more green so you would probably get some of them every day." Suggests Level 2 in the substrand.