Addition and Subtraction
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One of the most difficult areas of arithmetic to master for many is place value. At least
twice a year I’m asked how we “did” it, as though I have some magic formula that will
take the knowledge and, overnight hopefully, implant it firmly in a child’s brain. Sorry, I
don’t have that, wish I did though
I have always liked the idea of manipulatives but I am about as cheep as they come. I
have only purchased two kinds: a large bag of marbles for the 99-cent store and an
inexpensive poker set to get the chips. For this, you’ll need the marble-type
manipulative. Something that is small, about the size of a penny, in fact pennies work
very nicely as you’ll soon see. You just need about 40 of the exact same item.
One of the reasons I didn't get the store-bought, cute manipulatives that look like bears
or fire engines is that they are all different colors. My son is a sorter and would have
spent more time sorting them into colors and then assigning each color a unique value
than actually DOING the math I wanted him to learn.
You are also going to need a few strips of felt. They should be around 1” wide and
about 8” long. You need 11, each a different color. You can use other fabric if you are
using pennies or a similar flat item as your manipulative. Anything that flops or rolls, go
with the felt.
You need two file folders (used ones are fine), some glue like white school glue, and a
black marker.
Materials List Again:
1. 40 same size manipulatives, about the size of a penny
2. 11 strips of felt, 1” x 8” in size, all different colors
3. 2 file folders
4. white school glue
5. black marker
Take a look at the finished product you’ll be making, before we get started.
Start by gluing the two file folders together. You want them to overlap in the back and
have the two “flaps” act as a cover for your finished board.
Next you’ll glue down the felt strips. Start on one side or the other and glue them down
side by side.
When you finish gluing down the felt strips, you’ll have a rainbow attached to your file
folders. The double layer helps to handle all that glue you just used.
Time to add the numbers. We’re going to assume you are teaching Base-10 math (0 –
9). I mention this because you CAN use this board to learn other numbering systems. I’ll
explain that in the end notes.
So you label the first felt strip “1”. This is the strip all the way to the right. Put a number
1 on the file folder flaps above and below the first felt strip.
The next felt strip to the left is “10” – as in the 10’s place. Then comes “100”, “1000”,
“10,000”, “100,000” and so forth. Put the numbers below and the words (tens,
hundreds, thousands and so forth) up top.
Your board is now finished and, after the glue is dry, ready to use.
Putting It To Use
Grab some manipulatives and work this with me. Our first number is 18. So put 1
counter on the “10” felt and 8 on the “1” felt.
We want to add 5 to this. So take five counters and add those to the “1” felt. Notice you
now have more that 10 on the “1” felt? Take out ten and leave the rest. You have one
more ten (the ten that you removed from the “1” felt), so add one to the “10” felt. You
should have two on the “10” and three on the “1” – or 23.
To make sure YOU know how to use the board, leave those counters in place and to
them add 79. Work out the answer before looking at the picture.
twice a year I’m asked how we “did” it, as though I have some magic formula that will
take the knowledge and, overnight hopefully, implant it firmly in a child’s brain. Sorry, I
don’t have that, wish I did though
I have always liked the idea of manipulatives but I am about as cheep as they come. I
have only purchased two kinds: a large bag of marbles for the 99-cent store and an
inexpensive poker set to get the chips. For this, you’ll need the marble-type
manipulative. Something that is small, about the size of a penny, in fact pennies work
very nicely as you’ll soon see. You just need about 40 of the exact same item.
One of the reasons I didn't get the store-bought, cute manipulatives that look like bears
or fire engines is that they are all different colors. My son is a sorter and would have
spent more time sorting them into colors and then assigning each color a unique value
than actually DOING the math I wanted him to learn.
You are also going to need a few strips of felt. They should be around 1” wide and
about 8” long. You need 11, each a different color. You can use other fabric if you are
using pennies or a similar flat item as your manipulative. Anything that flops or rolls, go
with the felt.
You need two file folders (used ones are fine), some glue like white school glue, and a
black marker.
Materials List Again:
1. 40 same size manipulatives, about the size of a penny
2. 11 strips of felt, 1” x 8” in size, all different colors
3. 2 file folders
4. white school glue
5. black marker
Take a look at the finished product you’ll be making, before we get started.
Start by gluing the two file folders together. You want them to overlap in the back and
have the two “flaps” act as a cover for your finished board.
Next you’ll glue down the felt strips. Start on one side or the other and glue them down
side by side.
When you finish gluing down the felt strips, you’ll have a rainbow attached to your file
folders. The double layer helps to handle all that glue you just used.
Time to add the numbers. We’re going to assume you are teaching Base-10 math (0 –
9). I mention this because you CAN use this board to learn other numbering systems. I’ll
explain that in the end notes.
So you label the first felt strip “1”. This is the strip all the way to the right. Put a number
1 on the file folder flaps above and below the first felt strip.
The next felt strip to the left is “10” – as in the 10’s place. Then comes “100”, “1000”,
“10,000”, “100,000” and so forth. Put the numbers below and the words (tens,
hundreds, thousands and so forth) up top.
Your board is now finished and, after the glue is dry, ready to use.
Putting It To Use
Grab some manipulatives and work this with me. Our first number is 18. So put 1
counter on the “10” felt and 8 on the “1” felt.
We want to add 5 to this. So take five counters and add those to the “1” felt. Notice you
now have more that 10 on the “1” felt? Take out ten and leave the rest. You have one
more ten (the ten that you removed from the “1” felt), so add one to the “10” felt. You
should have two on the “10” and three on the “1” – or 23.
To make sure YOU know how to use the board, leave those counters in place and to
them add 79. Work out the answer before looking at the picture.
| Addition and Subtraction Place Value Board |
