Year One
Maths | Addition and Subtraction | Add and Subtract Numbers Mentally | Lesson 1 of 8: Addition and Subtraction Facts within 20
Addition and Subtraction
Success Criteria
Aim
•
Statement 1 Lorem ipsum dolor sit amet, consectetur adipiscing elit.
•
Statement 2
• Sub statement
Aim
•
To recall addition and subtraction facts within 20.
•
I can recall addition number facts within 10.
•
I can recall addition number facts that bridge 10.
•
I can work out the related subtraction facts.
•
I can apply these facts to solve problems.
Total 10
Do not total 10
Recall the answers to these facts
and sort them into the table.
Try not to use your fingers - see
Total is Odd
Total is Even
Recall the answers to these facts
and sort them into the table.
Total is < 5
Total is > 5
Recall the answers to these facts
and sort them into the table.
These are the number facts
we should have at our
fingertips. We should know
the
answers
to
these
calculations
without
counting on, using our
fingers or a number line.
Knowing these facts will
make
other
calculating
speedier!
+ 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10Goodness, that’s a lot of
facts! But I know some
things that can help me.
Can you make some
general statements?
When we add 0
to a number, the
number does not
+ 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10
Fingertip Facts
+ 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10That’s a few less to learn. I
know some other things
Which pairs of numbers add
together to make 10?
Odd:
1 + 2 =
3 + 2 =
5 + 2 =
7 + 2 =
9 + 2 =
What happens when we add
2 to a number?
Even:
2 + 2 =
4 + 2 =
6 + 2 =
8 + 2 =
10 + 2 =
0 + 10
1 + 9
2 + 8
3 + 7
4 + 6
5 + 5
10 + 0
9 + 1
8 + 2
7 + 3
6 + 4
even number
+ 2 = next even number
odd number
+ 2 = next odd number
Remember
addition can be done in any
order - it is commutative. So,
we know these facts the other
way round too.
+ 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10 + 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10
I know some
doubles. That will
help too!
Let’s add those facts
we know too…
What doubles do we know?
1 + 1 =
2 + 2 =
3 + 3 =
4 + 4 =
5 + 5 =
6 + 6 =
7 + 7 =
8 + 8 =
9 + 9 =
10 + 10 =
We can use these doubles to
help with near doubles.
2 + 3 =
3 + 4 =
4 + 5 =
5 + 6 =
6 + 7 =
7 + 8 =
8 + 9 =
For near doubles we recall our
double facts and add 1 more.
+ 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10 + 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10
Let’s think what else
we already know.
Let’s add those facts
we know too…
Can you make some
general statements?
+ 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10 + 0 1 2 3 4 5 6 7 8 9 10 0 0+0 0+1 0+2 0+3 0+4 0+5 0+6 0+7 0+8 0+9 0+10 1 1+0 1+1 1+2 1+3 1+4 1+5 1+6 1+7 1+8 1+9 1+10 2 2+0 2+1 2+2 2+3 2+4 2+5 2+6 2+7 2+8 2+9 2+10 3 3+0 3+1 3+2 3+3 3+4 3+5 3+6 3+7 3+8 3+9 3+10 4 4+0 4+1 4+2 4+3 4+4 4+5 4+6 4+7 4+8 4+9 4+10 5 5+0 5+1 5+2 5+3 5+4 5+5 5+6 5+7 5+8 5+9 5+10 6 6+0 6+1 6+2 6+3 6+4 6+5 6+6 6+7 6+8 6+9 6+10 7 7+0 7+1 7+2 7+3 7+4 7+5 7+6 7+7 7+8 7+9 7+10 8 8+0 8+1 8+2 8+3 8+4 8+5 8+6 8+7 8+8 8+9 8+10 9 9+0 9+1 9+2 9+3 9+4 9+5 9+6 9+7 9+8 9+9 9+10 10 10+0 10+1 10+2 10+3 10+4 10+5 10+6 10+7 10+8 10+9 10+10
Let’s look at
what’s left.
Let’s add those facts
we know too…
These are the facts left to learn.
Can you
think of any strategies
to make these easier to
remember? Share your ideas.
We know addition and
subtraction are inverses.
What does this mean?
Addition and subtraction
are opposites. One can
undo the other.
When we can
recall addition
facts instantly, we
How many of these addition
facts can you remember?
Challenge yourself to remember
them all in 5 minutes.
If you have time to spare,
start writing some related
subtraction facts on the second
half of the sheet.
Dive in by completing your own activity!
Success Criteria
Aim
•
Statement 1 Lorem ipsum dolor sit amet, consectetur adipiscing elit.
•
Statement 2
• Sub statement