7) Addition and Subtraction Ideas

Roll the Dice – KS1
Two dice are RED and one is GREEN.
Roll the dice and add up the numbers on
the two RED dice and then subtract the
number on the GREEN.
What are all the different possible answers?
Maze 100 – KS1/KS2
Can you find a way through in which the numbers add to exactly 100?
Reach 100 – KS2
You must choose four different digits from
box. For example:
1−9 and put one in each
This gives four two-digit numbers:
52 (reading along the 1st row)
19 (reading along the 2nd row)
51 (reading down the left hand column)
29 (reading down the right hand column)
In this case their sum is
151.
Your challenge is to find four different digits that give four two-digit
numbers which add to a total of 100.
A number in a little box is put into a wonderful big box that adds
something to the number and then a new number comes out at the end:
What was in the box? – KS1
The first time this happens, 10 is put into the little box, so what
happened in the big box to get the answer in the picture above?
Now three more boxes with new numbers in, go into the wonderful box
one at a time. It still does the same as before.
So, what were the three new numbers that went in? Remember that the
wonderful big box did the same for all four numbers that went in.
Dice games – KS1/2
Two player game.
Each of you draw a set of four boxes like this:
Take turns to roll the dice and decide which of your four boxes to fill. Do
this four times each until all your boxes are full. Read the four digits as a
whole number.
Whoever has the larger four-digit number wins.
There are two possible scoring systems:


A point for a win. The first person to reach 10 wins the game
Work out the difference between the two four-digit numbers after
each round.
The winner keeps this score. First to 10000 wins.
A square of numbers – KS2
Can you put the numbers
correct?
1 to 8 into the circles so that the four calculations are
Find the Difference – KS1
Place the numbers 1 to 6 in the circles so that each number is the
difference between the two numbers just below it.
e.g. 5 – 2 =
3
Weights - KS2
Imagine you have two of each of the 'weights' above.
Different combinations of the weights available allow you to make different
totals.
For example:
B+C=6
B+2C=15
A+2B+C=4
2A+B+2C+D=−10
The largest total you can make is
20 (check you agree).
The smallest total you can make is −60 (again, check you agree).
Can you make all the numbers in between?