P o l y m e r "S e a l s"

Click here for your free, trained Polymer "Seal" (ball and stand not included).

This is a VERY SIMPLE demo and one that requires almost no preparation. (Sounds great so far, doesn't it?)

Resealable Plastic Bags (sandwich size is great) Sharpened pencils Water A "catch" bucket or tray (just in case)

This is another good opportunity to have your class use their journals to "predict" what will happen when you stick the pencil through the water-filled plastic bag. Explain to them what you will be doing and have them write down 2-3 "predictions" in their journal.

Fill a plastic bag with water (add food coloring, if desired) and seal the bag. While holding the bag in one hand, take one of the sharp pencils and, using a twisting motion, push the pencil into the bag. Because the plastic bag is made of polymers, it will stretch and make a "seal" around the pencil, and let little, if any, water escape from the bag. (This is where the "catch" bucket comes in) You can continue to push pencils through the bag to see how many you can get in the bag before it breaks. Hopefully, your bag will look something like this.