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## 'Up, Down, Flying Around' printed from http://nrich.maths.org/

Watch the video below to see how to play the Balloon Game.

*If you can't see the video, click below to read the rules.*
This is a game for two players. Each places their balloon on the game board, pointing to zero:

You have two piles of cards; operation cards (add/subtract) and number cards (-9 to +10).

A positive number is equivalent to puffs of hot air; if you add hot air to your balloon you will rise, and if you subtract hot air you will sink.

A negative number is equivalent to sandbags; if you add sandbags your balloon will sink and if you subtract sandbags your balloon will rise.

Take it in turns to turn over an operation card and a number card. For example, if you turn over

**add -7**, this is like adding 7 sandbags, so your balloon will move down 7 spaces.

To win, you either need to get to the top, or you need to be afloat when your opponent sinks to the bottom.

To play the game, you will need to print out the following:

Game Board

Balloons
Number and Operation cards (print out two sets of these and shuffle them together).

Alternatively, you may wish to play with these:

Alternative Number and Operation cards
Here are some other games you can play with the number cards:

**Alternative Balloon Game**
Take two operation cards and two number cards, and choose how to arrange them to give you maximum lift (or minimise your sinking!). You may need a larger winning target than 20 for this game.

**Highest Totals Game**
Shuffle the number cards and operation cards. Each player is dealt three number cards and two operation cards. Arrange them to make the highest total you can. The winner gets one point; first to 10 points wins.

Variation 1: Deal each player four number cards and three operation cards.

Variation 2: As above, but arrange the cards to get as close to zero as you can.

**Throwing Away Zeros**

Deal six number cards to each player.

When it is your turn, you can combine cards with operations of your choice to make zero. (For example, you could discard -7, 3 and -4 because -7 + 3 - -4 =0).

At the end of your turn, take ONE card from the pack.

The winner is the first person to get rid of all their cards.