# Maths

Today, in our live lesson, we are going to be adding and subtracting 2 digit numbers.

Have a look at the number sentence 23 + 12 = How could we work out the answer?

There are many ways to work it out. We could use a 100 square. We can start on 23 and jump down the one 10, that is in 12, to 33 and then jump forwards 2 to add the 2 ones. We land on 35 so 23 + 12 = 35.  See the example below. We could also use a number line. We can start on 23 and make a big jump to add 10 which is 33. Notice that 1 has been added to our tens number as we have added 1 ten.  Then we need to make 2 small jumps to add 2 ones which is 35.  See the example below. We could also work out the answer by drawing the diennes. I can draw 2 long tens to represent the 20 in 23 and 3 ones to represent the 3. Now I need to draw the 12. So I can draw 1 long ten to represent the ten and 2 ones to represent the ones. How many do I have altogether? See the example below Now have a look at the subtraction sentence 35 - 14 =

There are many ways we can answer this too. We could use a 100 square. We can start on 35 and jump up one 10, that is in 14, to 25 and then jump back 4 to take away the 4 ones. We land on 21 so 35 - 14 = 21.  See the example below. We could also use a number line to subtract. We can start on 35 and make a big jump backwards to subtract 10 which is 25 and then take 4 small jumps back to subtract the ones. We land on 21.  See the example below. We could also work out the answer by drawing the diennes. I can draw 3 long tens to represent the 30 in 35 and 5 ones to represent the 5. Now I need to take away the 14 by crossing out 1 ten and 4 ones. How many do I have left?  See the example below Today your mission is to answer the addition and subtraction questions on the mild, hot or spicy sheets below. You can answer them in any way you choose it is up to you. Find the answer and colour in the sheets. What picture will be revealed?

We also have some online games for you to complete if you would like to have a go.

Can you add the 3 numbers together before the balloons fall to the ground?

This game involves subtracting using the bar model.
Have fun!
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