We all know children need practice with column subtraction. But giving them plenty of opportunities to practise doesn’t have to mean working through a page of calculations.
A simple game can give us the practice we’re looking for, alongside opportunities to talk about place value, spot mistakes, explain choices and try out strategies.
That’s how I’d use Biggest Take Away. With a few pauses for discussion and a small change to the rules, this printable game can become the starting point for a whole lesson. Click here to see my Youtube video where I share how I would use this for a whole maths lesson or keep reading to find out more.
The lesson follows a simple structure: model, play, discuss, adapt and play again.
Choose whether your children will work with 2, 3, 4 or 5-digit numbers. You can use the same game across the class while adapting the size of the numbers to suit different children.
You’ll need the printable game sheet, a dice (12-sided preferrably) and something to write with.
This lesson is designed to be used with children who already have an understanding of how to do column subtraction. If they don’t, I would advise planning a lesson to explore this first. Before playing, very simply tell them how to play the game, without modelling too much; remember, we want the learning to come from them. It’s important to keep the instructions simple, just tell them how to play, not how to complete the subtraction question.
Children play with a partner, each rolling the dice to generate two numbers. For this first round, ask them to write their digits in the order they roll them then use column subtraction to find the difference. Partners compare their answers using >, < or =, and the player with the greatest difference wins a point. If their answers are equal, they both score a point.
Then they play again.
The game gives children a reason to calculate carefully: their answer decides who wins! Build in time for partners to check each other’s calculations before awarding the point.
While they’re playing, you can move around, listen to their conversations and look at their methods. You’ll soon see who is confident, who needs a reminder and who could benefit from working through another example with you.
There’s a lot we can learn from what children do during a game.
Someone might line up their digits incorrectly. Someone might put the smaller number on top. Another child might subtract the smaller digit from the larger digit in each column, regardless of which number it belongs to.
These are useful opportunities to pause the game and explore what’s happening.
You might ask:
“Talk me through what you did here.”
“Can you show me that exchange using a place value drawing?”
“You’ve found the difference. How could we use addition to check it?”
We don’t need to jump in with the answer straight away, but we do need to help children make sense of their mistakes. A question, a drawing or another modelled example can help them understand what needs to change and why.
For this game, we put the greater number first to find a non-negative difference. That’s more precise than telling children that we can never subtract a greater number from a smaller one.
After around 10 minutes, bring everyone back together.
By now, children will have completed several calculations, compared their answers and probably started thinking about why some differences are much greater than others.
Ask:
“If you want the greatest difference, what two numbers would you hope to roll?”
Give partners a moment to discuss it, then share their ideas.
You could explore:
Write 654 − 632 and 621 − 123 on the board.
Which will have the greater difference? Can children explain their choice before calculating?
This is where the game opens up a useful discussion. Winning depends on both numbers: a large starting number won’t help much if you subtract almost all of it!
Now introduce a twist:
“This time, you can choose where to put each digit you roll.”
Children can place each rolled digit in any empty space in either of their two numbers. Once a digit is written down, it must stay there.
The aim is still to create the greatest difference, but now they have decisions to make.
Where should a high digit go? Where might a low digit be useful? Should they fill a space straight away or save it and hope for a better roll?
You might hear:
“I’m putting my six in the hundreds column of my top number.”
“I want a small number underneath, so I’m saving that space.”
“I thought I’d roll something smaller, but now I have to use this!”
They’re still practising column subtraction, but they’re also using place value knowledge, making predictions and explaining their choices.
Bring the class back together for a short final discussion.
Ask children to share one calculation and explain a decision they made. Did their strategy work? Would they change anything next time?
You could finish with:
“What advice would you give someone who wants to win Biggest Take Away?”
Look for explanations that connect the strategy to the maths, such as placing higher digits in the higher-value columns of the top number and trying to keep the number being subtracted small.
For a quick individual check, ask each child to complete one final subtraction and explain how they know their answer is reasonable. This helps you see what they can do independently after the partner work.
Across the lesson, children have generated calculations, practised column subtraction, checked answers, compared numbers and explored how place value affects the difference.
And you’ve had opportunities to model, question, address misconceptions and decide what they need next.
That’s what I love about using games in maths lessons. A small change to how we organise practice can give children so much to think and talk about.
Biggest Take Away is available to download as part of the Playful Learning Games membership, with options for 2, 3, 4 and 5-digit numbers, so you can choose the right starting point for your class.
You can also take a look at my other printable calculation games here.
