Teaching techniques – using metaphors for conceptual understanding.

Teaching slightly confusing concepts is not an easy task. At such times using metaphors comes in handy for the teacher. Unfortunately, I have come across very few teachers who use metaphors to teach or explain a concept in the class.
Using metaphors is using a familiar concept to teach the unfamiliar. It is making the unfamiliar familiar. We pick a totally unrelated but well-known idea and point out similarities between the well-known idea and the new idea.
In one of the English classes I had to explain the concept of Homonyms, Homophone and Heterophones – words with same/different spelling and same/different pronunciations and of course different meaning. After thinking for a while I stuck on the concept of twins. Twins can look identical or can look different. I projected the idea to the words. The concept became immediately clear to the students. See the post here:
In another class on Anger Management, I borrowed the metaphor of a firecracker from another author. The fire-cracker has ammunition, a fuse and needs to be lighted to explode. Anger could be connected to it by showing that there is a trigger (lighting up), a time lapse (the fuse) before the ammunition blows up (a person gets angry). To prevent the ammunition from blowing up (getting angry) either the lighting it up (trigger) is avoided or the fuse is lengthened(borrow time). Now the concept of anger management becomes clear. You have used a familiar (fire-cracker) to make the unfamiliar (anger management) familiar.
When looking for a metaphor keep few things in mind. Be clear about the concept to be taught. Choose an appropriate metaphor. List the ways the metaphor fits your concept. Note the ways the metaphor does not fit the concept (where there are discrepancies between your metaphor and the concept you want to teach) so that you can bring out the differences too in the class. The metaphor must be simpler and well known compared to the concept being taught.
But always remember that it is only a metaphor and metaphors have their limitation. The metaphor is not the real thing. Once the concept is understood throw away the metaphor. The metaphor is the scaffolding used to construct the building. Once the building is done, the scaffolding is discarded. There I have used another metaphor to explain the use of metaphor!