Special Assignment

I can't say for sure why I missed the metaphor. Especially since my first thought when looking at the cartoon was they look like the the Mac commercial guys."> I thought maybe he is using them like a spoof. I guess I just over thought it.
Metaphors
1. It is easier for a camel to go through the eye of a needle than it is for a rich man to get into heaven. 2. Better to beg forgiveness than to ask for permission. 3. We waited a lifetime. 4. Let your light so shine before man that he may see your good deeds. 5. The Giving Tree by Shel Silverstein
Helping Students Understand
I think the best way to help them understand is to use them. Then ask Do you know what that means? Have a discussion about how they interpreted it and why they thought the way they did.Maybe get them to make up their own and get their classmates to see if they get the meaning.You could get them started with something like... playing outside is... "Let the kids run with it" and see what happens.
Why we use Metaphors.
Metaphor - a figure of speech in which a word or phrase literally denoting one kind of object or idea is used in place of another to suggest a likeness or analogy between them (as in drowning in money) (Webster) We use metaphors to get a point across. They are often used to convey sarcasm. They are sometimes used as a comparison of two unlike things.