Imagine all the place value warm-ups you can do with this photograph from Sydney harbour of a 5-digit number, 21872. If you re-arrange the digits, what is the largest number you can make? The smallest? The second largest? What are 2 numbers this one is between? 2 more? 2 more? What is 20 000 less than this number? What if I add 100 000? Is it odd or even? How do you know? If this was how many litres of water you have, how many tonnes is that? If this number was how much money you have in the bank, can you buy a car with this? If so, which one? How many 10s in this number? How many 1000s? How many in the hundreds place? What is 10 times larger than this number? 10 times smaller? 100 times smaller? What have we forgotten to ask????