Year 5 Explaining, convincing and proving

Think of a number, square it and subtract your starting number. Is the number you're left with odd or even? How do the images help to explain this?

Do you agree with Badger's statements? Is Badger's reasoning 'watertight'? Why or why not?

Investigate the sum of the numbers on the top and bottom faces of a line of three dice. What do you notice?

Can you put these four calculations into order of difficulty? How did you decide?

Can you find out which 3D shape your partner has chosen before they work out your shape?

Choose four different digits from 1-9 and put one in each box so that the resulting four two-digit numbers add to a total of 100.

Find the product of the numbers on the routes from A to B. Which route has the smallest product? Which the largest?

This challenge combines addition, multiplication, perseverance and even proof.

Can you order the digits from 1-3 to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on?

Look at what happens when you take a number, square it and subtract your answer. What kind of number do you get? Can you prove it?

Try out these calculations. Are you surprised by the results?

Use your knowledge of place value to try to win this game. How will you maximise your score?

How much can you read into a T-shirt?