It All Adds Up To Zero

I was subbing in a grade 5/6 class and the teacher had the students playing a very simple dice game to get them to add negative and positive numbers.  I tried to search for it online (she was calling it "It All Adds Up To Zero") but I didn't find anything... if you do know of a link add the link in the comments below!

Anyways, here is what you'll need (for each pair of students)

- one deck of cards with the kings, queens, and jokers removed

- one pencil

- 2 pencil crayons that are different colours

- 2 dice

- a piece of paper to draw out the board (or you could make one and print it off for them)

The board game would be simple enough to make (they could even use graph paper) just print off a sheet with squares on it and have them block of a playing area and an area to keep track of their scores.

How to play:

When it is your turn you turn over 2 cards.  Red cards are positive numbers and black cards are negative.  Also, a jack is 0 and an ace is 1.

You look at the 2 cards and decide which number you would like to write down (using your pencil) on the board any where you like (for the first player it really doesn't matter where you write your number).  Just make sure you write down the negative sign if it's negative!

Second player turns over 2 cards and chooses one to write down... this one doesn't really matter where you write it either (you'll see why in a minute)

Now it is back to the first player and they turn over 2 cards and choose one to write down.  The point of the game is to get 3 or more numbers in a row that will add up to 0 (horizontally, vertically, or diagonally).  So say you had a -3 and -4 already beside each other written down on the board and you happened to turn over a +7 (or a red 7) if you write it down beside the other 2 numbers you could circle them (in the colour of pencil crayon that you want to be yours) because those numbers all add up to 0 and get 1 point.  

Now that those 3 numbers are circled you cannot use all 3 of them again to make a longer set of numbers that add up to 0 (say you got a jack which is 0... even if you placed it beside the already existing chain you couldn't count it as another one).  You could use one number from that chain again in another one though.

You don't have to only make sets of 3... but the minimum number of numbers you need are 3.

When the space is filled up with numbers you can count up your points and see who won!

Easy!

(boy I hope this made sense... if it didn't let me know in the comment section and I'll do my very best to answer all of your questions).