The temperature of the liquid water is reduced below its freezing point, without becoming a solid. The ice wont form without the presence of a nucleation point (a crystal or impurity around which an ice crystal can begin to grow). However, on contact with another surface, the water instantly freezes. Check out how to make instant ice at home in this video: http://youtu.be/sBFK5-JvBAc
Why? Stencils are an excellent tool for rapidly reproducing the same design over and over again. The process can be done simply by cutting away from a piece of material like cardboard, plastic, or even paper. Once paint is applied, it moves through the cutout and onto your surface of choice – revealing a sweet design! Stenciling began in the prehistoric period when hands acted as stencils on cave walls. Today intricate stencils are used by many street artists to tell their story in public places.
What else? Stencils make a great tool for visual storytelling. Design a stencil that sends a message to others, and display that message publicly. More curriculum connectors can be found here.
Image description: This is an animation of the Aurora Australis (Southern Lights), eight days after a record-setting solar flare sent a shower of charged particles towards Earth. From Earth, this glowing ring would appear as a curtain of light shimmering across the night sky.