Objective: The Red & Blue Rods teach numeration. They indirectly familiarize the child with the metric system.
Note: The concept taught is slightly different from the concept
of numeration taught by the Cards and Counters type of work, for
instance. The Red & Blue Rods teach the number 4 as a unit
which is four times larger than the one unit. Whereas the Cards
and Counters teach that there are four single units in the number four.
It is useful for a child to understand both concepts of a number.
Ages: 3 - 5 years
Control of Error: The set of rods will be the same length when the equation is properly balanced.
Presentation: Roll out a rug and select the rods from the shelf
one rod at a time - carefully. Lay the rods on the rug in no
particular order. Starting with the one rod, lay the rods in
order. Check that the next rod selected is the proper rod by
using the one rod at the end of the next smallest rod. For
instance, if you are laying down the seven rod and want to show that
the seven rod comes after the six rod, you take the one rod and lay it
at the end of the six rod and see that the length of the two lines of
rods are the same, 6 + 1 = 7. During the presentation you may
want to show the control of error by checking with the one rod as
described above and finding that the rods are not the same length, then
search for another rod and check it against the x+1 rod.
Presentation 2: Addition to the sum of ten is possible 9 (and
fun) with the Red & Blue Rods. To demonstrate the addition
question "3 + 1" take the three rod and the one rod, lay them end to
end. Then take the four rod and lay it beside the three and one
rods, showing that the answer is four because the three and one rods
together are the same length as the four rod.
Extension: Lay out a ten rod and find all of the rods which will
add up to ten. The equation is balanced (correct) when the set of
rods are the same length as the ten rod.
Creating the Material: There are several sizes and types of red
& blue rods. All were created at home by Polestar Private
School.
Materials List - Set 1:
5.5+ meters of 1" square wood (I got mine from Home
Depot and you may need extra)
primer
red gloss paint (I use Krylon enamel)
blue gloss paint
paint brush
Cut the rods into the appropriate
lengths: each unit is one decimeter (10 centimeters). So
for the seven rod you will cut a piece which is 70 centimeters in
length. Next, prime and paint the rods. The one rod is red,
the two rod is red then blue, the three rod is red, blue, red, etc.
Each color is one decimeter long.
Materials List - Sets 2 & 3:
Print the Red & Blue Rods file Set 2 or Set 3 onto cardstock or photo paper. Laminate if desired.
Set 2 is used the same as Set 1. Set three is designed to be used with the Addition Strip Board.