Liquid or Solid??

Today I put students to the test to figure out whether my "mystery substance" was a solid or a liquid! Sounds easy enough, however our mixture seemed to be showing characteristics of both solids AND liquids. We have been learning about the characteristics of solids and liquids, and students argued their thoughts very well:

   Reasons why they thought the mystery substance was a solid:
                          - You could pick pieces of it up out of the container
                          - The pieces kept their own shape for a little bit
                          - When you hit the substance with your hand it was hard
         
   Reasons why they thought it was a liquid:
                         - When moved slowly it "flowed" like a liquid
                         - It took the shape of the container it was in
                         - You could stick your finger right into the substance like water
                         - It dripped off your hands
                     
   The "Mystery substance" was Oobleck, which is a combination of Corn Starch and water. This mixture is special because it can act both as a liquid AND a solid. It is a liquid in it's resting state, and turns into a solid when pressure and force is applied. I have included a couple pictures of our activity below as well as a link to a youtube video that shows you what Oobleck is and how to make your own.

Video:  Oobleck Instructions


  Mrs. Miller