My son's 5th grade class studied Solutions in science. At the beginning of the year for open house the teacher mentioned the topic I had recently seen the PopSci post and a Make post about a super saturated Sodium Acetate solutions and was looking for an excuse to play. The teacher was interested but when I offered to prepare the supplies for her to demonstrate she suggested I come in and give the demo. I accepted.
I ordered my crystallized sodium acetate from United Nuclear. Look for reruns of Wired Science to see a story about them. I later realized making the crystals from Baking Soda and Vinegar at home is very simple and much cheaper.
For the class presentation after I did the demonstration showing the clear super saturated solution turning into a solid as I poured it out I shared what was occurring and the chemicals involved. Asking who had made sodium acetate at home resulted in silence and blank stares. I followed that with the recipe of mixing sodium bicarbonate and acetic acid. Again blank stares. I said let me demonstrate. As soon as I poured the vinegar into the baking soda they all knew exactly what it was.