Challenge Level

**Why play this game?**

**Possible approach**

Give them chance to talk in pairs about the possible rules. Emphasise that they may not be completely sure and that is alright. They may even have some questions to seek clarity. After a suitable length of time, show the video again so that learners can check their initial thoughts.

Then bring everyone together and reveal the rules of the game on the screen by clicking the 'Show' button in the main problem page. Try to keep silent yourself (other than reading out the rules) and then give learners chance to talk to their partner again.

Next you can show them the following video, which does have sound, and so explains how to play:

Facilitate a whole group discussion in order to agree on the rules, and once everyone is clear, give pairs a copy of the game board each and a counter. Allow them time to play the game several times without saying much more yourself. It is important that learners are able to 'get into' the game before being expected to analyse it in detail.

You could then invite the group to begin to think about good ways of winning (if they haven't done so already). At this point, you could put them in groups of four so that they play two against two. This gives them the opportunity to discuss strategy with their partner.

The session could culminate in the creation of a list of 'top tips' for anyone playing this game and wanting to win.

See also the possible adaptations sent in from one class.

**Key questions**

Where

What might your opponent do then?

Tokyo class at Manorfield Primary School, London, came up with some wonderful adaptations to the game.

Renah and Sami played so that you could choose any calculation. They removed the "bust" rule which meant that players could be mean and multiply the number far beyond the target number! They then thought about using more than one move a turn. They could then use brackets to change the order of operations and come up with more possibilities.

Rumaysa and Chloe introduced a minimum target number in order to make the games last longer.

Adil and Ahsanur added the choice of moving 1,2 or 3 times. They also got to choose which calculation to use. They found it annoying when someone was able to multiply by 0 and had to start again!

Samah and Khadija took it in turns to reach the target number with the fewest moves. They noticed the person that went second had an advantage.

Sameeha and Anaum made a decimal number version of the game. They turned the numbers into tenths. They then could change their target numbers into decimals.

Humairah and Aayana changed the rules so that any even number on the board you have to subtract and odd numbers you add. This became annoying when you were close to a number but an even number away, so then you would have to subtract.

Alex and Faisal added digits up to 9 on the board and made the playing board larger. This made it easier to get bigger numbers quicker.

**Possible extension**

- What is the shortest 'string' of numbers that adds to their chosen total?

- How many different 'strings' of numbers that add to their chosen total can they find?

- Could they design a different grid to make the game harder/easier? (Here are blank boards which may be useful: Word document, pdf.)

- What if the grid contained decimal numbers/fractions?

You could introduce the game Play to 37 as a follow-on to this one.

Martin Shaw who teaches at Seal Primary Academy in Selsey suggested the following:

- Play the game cooperatively i.e. both players work together to try to reach 20.

- Start at 20 and subtract the numbers on the grid to try to get to 0.

**Possible support**