A new model explaining this mysterious process suggests the core was created as dribs and drabs of iron percolated inward from Earth's lower mantle, according to a study published Oct. 6 in the journal Nature Geoscience. The mantle is the viscous, rocky layer between the crust and Earth's iron core.
Definition of flash card. : a card bearing words, numbers, or pictures that is briefly displayed (as by a teacher to a class) usually as a learning aid.
Flash cards are a simple, versatile, yet often underexploited resource. I would like to offer some reasons for using flash cards and a selection of activities for use in the Young Learner classroom, although some of the activities could also be used with fun-loving, lower level adult classes. In this article there is one example for each type of activity.