Have you seen the new Crayola Crystal Effects Window Markers? You can draw on windows with these markers. Better yet, you can use these markers to teach students some chemistry! After drawing on a window with these markers and waiting a little while, the marker ink appears to crystalize! Check out the video below to see how they work.
Tom Kuntzleman's blog
Have you ever cooked a marshmallow in a microwave? In case you are not familiar with this experiment, when a marshmallow is heated in a microwave, gases trapped in the marshmallow expand and escape. When the gas molecules escape from the marshmallow, they push against the marshmallow, causing it to expand. To see this experiment, play the video below.