OK Barbara, how are you today?
I'm good, how are you Michelle?
Very well thank you. I thought today we could play one of my favourite games of strategy that you can play pretty much anywhere. Ok. So we just call it the counting game.
You can play it in lots of different ways using any number that you like. So today to get us started. I'd like you to think about the target number.
Let's make it. We want to count by fives today so it has to be a number that would be in the counting sequence by fives. And your favourite two digit number. Oh I have lots of favourite two digit numbers, but my favourite today is 85. So I know that's going to be a five number 'cause it ends in a five by five or zero, so 85 is our target and then we play it just by counting together all the way up to 85.
But when you count, you can either say one number word, two number words or three number words. So you could say five or five, ten or five, ten, fifteen. Ok. We take it in turns and you win if you're the person that gets to say the target number. And I should say it because I chose it.
I'm hoping to get. Yeah. Ok. And because we're mathematicians. We're also going to record our thinking so when the numbers that you say I'll record that in my marker and you can record my moves too, so let's just have a go and you'll learn through playing.
Can I start?
Of course.
I'm going to say . five, ten.
Alright, I'm going to say fifteen, twenty, twenty-five and ok where do I write that? Underneath. Ok.
OK. Your go.
Of course. I will say thirty, thirty-five, forty.
I will say 45.
I wonder why you only choose one? I'm going to say fifty, fifty-five.
Sixty.
Just sixty. Now we're getting quite close, so I think that now I need to start really thinking about this. But because it's a new game I think because I'm not sure what to do next, so I'm going to say.
Oh, hold on a minute. I'm thinking now that if I get you to close, you'll be able to win, so I don't want to get you that close. So I don't want you to say OK. I'm only going to choose a few numbers to so I can. Ok. keep thinking about this sixty-five. Ok.
And I'm going to say seventy.
And I am going to say... I'm very excited because I can say seventy-five, eighty, eighty-five. Which means I win! Congratulations, you're the winner today. Wow, but now that we've got our recording, we could also go and investigate. Is there a way that you can either guarantee you win or at worse that you never lose? Yeah, of course. Off you go let's go see what happens. Let's explore.
You will need:
pencils or markers
your mathematics workbook.
Select a target number for example, 85.
Then select a unit value for example, fives.
The goal is to be the player who says the target number.
Players can count on by saying the next 1, 2 or 3 number words in the fives sequence.
Players collect a counter (or a tally mark) if they say the target number. A new target number is chosen and players play again.
For example:
Target number 85
Player A : 5, 10,
Player B: 15, 20, 25...
Player A: 30, 35, 40...
Player B: 45...
Player A: 50, 55
Player B: 60
Player A: 65,
Player B: 70, 80, 85!
Player B collects a counter (or tally mark!)
Is there a way to play so that you never lose?
I wonder if Michelle could have changed her moves in any way to win. Could you give Michelle some advice? If she had said different number words, how could she have won?
Share your work with your class on your digital platform.
You may like to:
share your responses to the reflection questions
write comments
share pictures of your work
comment on the work of others.