If you want your students to think creatively teach them.  This article gives some examples with the main idea being if you want them to think creatively you need to provide examples.  Many years ago I used this method in simplified form in high school and middle school.  Early elementary teachers tend to do it automatically.  See. http://library.curriki.org/xwiki/bin/view/Coll_VirginiaMaloneet/AdvertisementActivity for a high school activity and the importance of examples.

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