Transcript Maths Presentation

Growth, hospitality and service in Christ
St Kevin’s Catholic
Primary School
Prep-2 Maths Information Night
ACTIVITY ONE
What do students need to be able to do?
FOUNDATION LEVEL
 Count forwards/backwards
from 0-10 initially, then to 20
 FNWS/BNWS not starting from
zero.
 Match number names, digits
and quantities
 Subitise
 Compare and order
Counting
To count effectively, children not only need to know
the number naming sequence, they need to
recognise that:
•Counting objects and words need to be in one-to-one
correspondence;
•You have to say 1, 2, 3, 4 in the same order each time
•The order in which the objects are counted doesn't matter.
The child can start with any block and count them.
•“Three” means a collection of three no matter what it
looks like
•The last number counted tells ‘how many’
Trusting the Count
Initially, children may not believe that if they
counted the same collection again, they would
get the same result, or that counting is a
strategy to determine how many.
Trusting the count is evident when
children:
 Know that counting is an appropriate response
to “How many……?” questions
 Believe that counting the same collection
again will always produce the same result
irrespective of how the objects in the
collection are arranged
 Are able to subitise
Subitising
 Immediately knowing how many items lie
within a visual scene for a small number of
items.
 It is a fundamental skill in the development
of number sense and will help in the ability
to add and subtract as well as recall number
bonds quickly.
 For example, when a dice is thrown the
observer at a glance, immediately and
accurately knows how many dots lie on the
face of the dice without counting.
What do you see?
What can we learn from this?
We can learn:
•there are 5 dots.
•5 is more than 4
•5 objects can be separated in to a set of 2
and 3
•5 counters, no matter how arranged, still
retain the same numerical quantity
•The oral name for a set of 5 things is ‘five
What do you see now?
What do you see?
Fingers.....
Dominoes: Another way of subitising
Research shows us.....
 That children as young as two years of age can subitise
2 or 3 objects*. There is quite a lot of evidence that
babies and some animals* can do it too.
 Adults can subitise about 5 or 6 objects.
* of course they may not know the name of the number but they know how many there are as a quantity!
LEVEL ONE
What do students need
to be able to do?
 Count
forward/backwards
with confidence
What number is covered?
What number comes after 64? What is ten more than
65? What is the number before 75? After 75?
What else do they need to be
able to do?
Write numbers
Order numbers
ACTIVITY TWO
 Represent and solve simple addition and
subtraction problems using a range of
strategies
STRATEGIES
Counting On...
Generally this strategy is the first students are taught
and is the easiest.
Use this strategy if one of the numbers is 1, 2, 3 or 4
Begin with the larger number and count forward
For example, in the equation 5+3, you want students
to start with the “5” in their heads, and then count
up, “6, 7, 8.” This is to discourage students from
counting like, “1, 2, 3, 4, 5…..6, 7, 8.”
Counting On Strategy
6+3=9
0 1
2 3 4 5
6 7 8
9 10 11 12 13 14
Partitioning
 Helps students to visualise numbers
 Helps them to work out number sentences in their head
Pattern Cards
Partitions of Five
Partitions of five help students when solving addition
such as 7 + 5 = 12 because they know 3 and 2 makes
five, so they do 7 + 3 = 10 + 2 = 12
What do you see?
Seven and three
What do you see?
TEN FRAMES
How would we word this problem?
And the answer is........
49
What else can you do/ask?
 Complement to 10/20. I say seven you say how
many more to make 10?
 What two numbers make ten/twenty?
 Play Celebrity Heads
Re-arrange parts
26 + 5 = 25+5+1= 31
13 + 8 = 10 + 8 +3 (2+1) = 21
You Try:
134 + 7 =
130 + 7 + 3 + 1= 141
OR
134 + 6 + 1 = 141
Mental Strategies for Addition
PREREQUISITES
 Children know their part-part-whole
number relations (e.g. 7 is 3 and 4, 5 and 2,
6 and 1 more, 3 less than 10 etc.)
 Children trust the count and can count on
from hidden or given
 Children have a sense of numbers to 20 and
beyond (eg. 10 and 6 more, 16)
Model numbers using bundling sticks.
What does this mean?
How does this happen?
Conceptual Place Value
- Numbers are presented and discussed in their full
value: twenty as twenty or two tens; 21 as twentyone, or twenty and one
- Tasks involve increments/decrements in sequence.
For example, from 45, ten less is 35, ten less is 25,
one less is 24
- Solving tasks involves inquiry or problem solving
- Answering tasks might involve using knowledge of
the number sequence
Level Two
 Number sequences, increasing and decreasing, by
twos, threes, fives and ten from any starting point
 Working with numbers up to 1000
 Use previous strategies to solve problems up to
1000 (using hundreds, tens and ones).
Addition using partitioning
125 + 233= 358
Success Criteria:
 Step 1: partition numbers hundreds (100 + 200)
(tens 20 + 30) (ones 5+3)
 Step 2: add up the hundreds (100+200=300)
 Step 3: add up the tens ( 20 + 30 = 50)
 Step 4: add up the ones ( 5+ 3 = 8)
 Step 5: add all
(300+ 50 + 8= 58)
Empty Number Line using the
Jump Strategy
ADDITION PROBLEM: 37 + 45 =
SUBTRACTION PROBLEM
42 – 25 =
Arrow Cards
BUNDLING STICKS
154
Explore the connection between
addition and subtraction
• 10–9 = 1
• 10-1 = 9
 15 + 6 = 21
 21 – 6 = 15
Eight is Great – 2+8=10, 8+2=10, 10-8=2, 10-2=8, 10= 8+2,
10= 2+8, 10= ? + 8, ?=8+2
QUESTIONS?