Today we started a new engineering challenge Shrinking Shores.  We discussed erosion and watched some videos on erosion.  We came to the definition  of the movement of rocks, sand, or soil by natural forces such as wind or water.  Here is one of the videos we watched.   https://www.youtube.com/watch?v=ChEHQUMEkXw    Then we discussed how erosion affects wildlife?   We read a story where two kids are trying to save turtles habitats from erosion.  We discussed the term Wave: The movement of energy from place to place.  We then discussed how the energy in a wave most often comes from wind.  We talked about how a wave can be visible, such as in the side-to-side movement of a rope, or invisible, such as in the back-and-forth movement of sound waves.  But all waves move energy from one place to another.  Then we used ropes to see how force affects waves and their size.