How many guesses?

Steps

1. Ask how many house visits you would need to find a lent book among six houses. Everyone puts a prediction on a line.
2. Lay out the cards face down with a picture up. The numbers underneath are not in order.
3. Choose a target number. One child turns cards over until they find it. The class counts the guesses.
4. Repeat with other targets and record each count.
5. Look at the spread: sometimes lucky, sometimes the last card. On average, about half the cards.
6. Discuss how the number of guesses grows as the list gets bigger.

Talk about it

• Was it ever one guess? Was it ever all of them?
• What if there were a million cards?
• Could sorting the cards help?