What is place value? - Taipei European School

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What is place value?
Place value is a positional system of notation in which the position of a number
with respect to a point determines its value.
The decimal numeration system is based on base 10.
Each position in a number has a value that is a power of 10.
• http://www.linkslearning.org/Kids/1_
Math/2_Illustrated_Lessons/3_Place
_Value/index.html
Some
resources
you might
see being
used
http://www.teachers.tv/video/1435
Teaching place value
http://www.teachers.tv/video/1436
Parents workshop
http://www.teachers.tv/video/37862
Calculation lesson
Some games to play:
Guess my number-helps
understanding of less/more
than and use of 100 grid
Higher or Lower!
• This is a place value game which can be played with the whole
family.
• In pairs (to develop social / speaking-listening skills) draw 4
joined boxes in a horizontal line. Squared paper will help. The
‘teacher’ has a standard pack of playing cards with the
jester cards removed. They shuffle them, turn the top card
and call out the number. The others must choose a box to
write this number in. The cards are turned and called until
all four boxes are filled.
• Then display and say the number. People who get a higher
number than the ‘teacher’ gets 5 points. Equal to the
teacher gets 3 points. Lower than the teacher 1 point. The
teacher gets 10 points if he / she beats all the others!
• Matching numbers to their number names.
• Matching numbers to their tens and units:
156-how many tens, how many units etc.
• Ordering numbers. Order even and odd
numbers. Order numbers from 20-35 etc.
Time themselves.
• http://www.bbc.co.uk/schools/ks1bitesize/numera
cy/units/index.shtml
Place
Value
Call out the number
before the answer
appears.
When you
see it ,
say it!
First look at the tens
digit.
Two tens
are
twenty!
Next look at the units
digit.
Five units
are 5.
Two tens and Five
units = 25
Now it’s your turn,
but remember:
When you see it,
SAY IT!
Well Done!
You have worked hard
reading two-digit
numbers, now have a
go at reading three-digit
numbers.
Once you know
place value,
you will find
partitioning
numbers a lot
easier.
What strategies would you use to
add
2 two-digit numbers quickly?
• This is one way to do it.
• Split the tens.
• Split the units.
• Count on.
72+15=
• Split the tens.
• 70 + 10= 80
• 80+2=82
• 82+5= 87
Split the units.
43+56=
• Split the tens.
• 40 + 50= 90
• 90+3=93
• 93+6= 99
Split the units.
143+234=
• Split the hundreds. Split the tens. Split the units.
•
•
•
•
•
100 + 200= 300
300+40=340
340+30=370
370+3=373
373+4= 377
Work out the answers before the
questions disappear!
21+63= 84
45+51= 96
231+642= 873
How well did you get on?
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