Have you had the same problem as me? I teach
the vocabulary and characteristics of circles, to say a 12 year old, and then
perhaps two years later we have the same bright youngster and introduce the
concept of π. What went wrong they
couldn’t remember what the difference is between circumference, radius and
diameter? We really are struggling now, forget π, they can
barely remember the names yet alone what they represent. Yet year after year we
repeat the same mistake. I have developed these simple steps that have helped
improve my success rate.
Colour
How often do we ignore the use of colour
when teaching? Not only is it more cheerful than the usual drab black and white
it is a great aid to memory. Not too many colours otherwise it starts to look
like an explosion at a paint factory.
Circumference
I start with the circumference. I draw it,
in say blue, and now right the name underneath. But write it with a huge blue
circle almost swallowing the word explaining this is how you remember it
because the first letter of circumference tells you what it is.
Diameter
We now move on to the diameter. Explaining
what this is I draw my blue circle again but draw the diameter vertically in
red. Now I point out that the word tells you what the diameter it is just the
vertical in the D. Make sure you draw the D as a capital D.
Radius
At bit of human biology never goes amiss! I
tell them the bone in the forearm from the elbow to the thumb side of the hand
is called the radius. When drawing a circle on the board I explain that I have
to keep my elbow steady in one spot and move my arm to draw the circle. A
little demonstration helps. Next I introduce Homer Simpson, remember he only
has 3 fingers. I draw a circle draw the radius and with great artistic license
draw Homer’s hand waving at us showing his radius bone.
These ideas are simple, silly but they
really help in children remembering the names and concepts. I continue to use the colours and remain
consistent with their use. I encourage the students to do the same it aids
memory and understanding.
Does anyone else have a good tip?
Has anyone tried it and had success or
failure?
Make a comment and share your thoughts.