I've just started reading James Geary's I Is An Other, a magnificent book about the power and prevalence of metaphor. Surprisingly, he believes we use around six metaphors a minute - some of which are obvious, some of which are the skeletal remains metaphors which have become so commonplace as to be invisible. It's a fascinating book and excellent reading for anyone with an interest in language.
For me, it has proved inspirational. I've never seen metaphor taught as anything other than a literary device - and often this teaching has been dry and prosaic. Surely it would be better to give students a grounding in the everyday nature of metaphor before examining literary applications for it? If they realise how often metaphor is used in their daily lives - and by themselves - surely they'll be far better placed to understand it a more academic sense.
I'd anticipate the lesson taking an hour and the Powerpoint slides are not necessary at all unless you enjoy a little visual stimulus (or just like gazing at Elvis).
An Intro to Everyday Metaphor Plan
An Intro to Everyday Metaphor Handout
An Intro to Everyday Metaphor Slides