Why do this problem?
will help children explore and understand the concept of randomness. The interactivity will provoke much discussion, prompting learners to offer conjectures and justifications. The final part of the problem also brings in ideas related to ratio and proportion.
Share the interactivity with the whole class on an interactive whiteboard or project it onto an ordinary screen. Without saying anything, click on "Randomise" a few times, as suggested in the problem. Give children a minute on their own to think about how they would explain what this button does, then give them the chance to talk to a partner. Share ideas amongst the whole group and try to
come to a consensus.
Again, without talking, go on to the next part of the problem, giving them a chance to explain what they think might be happening. At some stage, somone will notice the small numbers written in some of the red squares, so you can discuss what they might mean and how this helps them to understand the interactivity.
You may want to continue in a similar way, or if you have access to a computer suite, children could use the interactivity directly. Make time for learners to offer conjectures about what might happen at each stage and encourage justification of them. The final part of the problem could be a follow-on lesson in itself.
Can you describe what is happening when I press "Randomise"?
Why does it take more than ten clicks to make all the squares red?
Can you explain why you think that?
Children can explore the full scope of the interactivity in more detail, for example by investigating how the accuracy of their estimations of an area might be affected by the trial size.
Some children will find it much easier to engage with this interactivity if they have a chance to manipulate it themselves.