Yes, it's Fall and Halloween will be here before you know it. Reader Linda Patton shares these recipes for physics-defying goop your students can make, play with and learn from.

FLUBBER
Borate solution:
2/3 cup warm water
1 1/2 teaspoon powdered Borax
3 drops food coloring
Mix together in a 1 cup measuring cup using a wooden spoon
Glue Solution:
3/4 cup warm water
1 cup white school glue
Mix together in a mixing bowl using a wooden spoon
Pour the borate solution into the bowl with glue solution. Use your hands to gently lift and turn the mixture until only one tablespoon of liquid is left. Flubber will be sticky for a moment or two. After the excess liquid has dripped off, Flubber is ready. Store in a plastic bag in the refrigerator. When you are through, discard in a waste can. DO NOT try to wash it down the sink. If it dries on carpet or clothing, cover it with a cloth soaked in vinegar to de-gel it, then wash the area with detergent and water.

GLARCH
Measure 1/2 cup liquid white school glue into bowl. I get the best results with Elmer's School Glue. Measure 1/4 cup Sta Flo liquid starch into the same bowl. Mix together with a wooden spoon. After the substance becomes too thick to use the spoon, continue mixing with your hands. This works quicker with warm hands. Glarch may be stored in a plastic bag. Wash all supplies.

OOBLECK
Measure 1 1/2 cups of cornstarch and put in a pie pan or container If you want a color of Oobleck add the coloring to the water first. Then gradually add approximately 1/2 cup of water to the cornstarch. Stir well (this will take some time). Add small amounts of more water or cornstarch until you get a mixture which 'tears' when you quickly scrape your finger through it AND THEN 'melts' back together again. Oobleck is often referred to as a 'non-Newtonian' substance because it does not behave as Newton's Third Law of Motion states; for every action, there is an equal and opposite reaction. Applying this principle, you would expect Oobleck to 'splash' when you 'smack' it with your hand. (Smacking is the action, splashing is the reaction.) However, when you try this out. Oobleck does not splash, in fact, it becomes a solid substance for a few moments. Why? Scientists explain this as follows. Uncooked corn starch particles are structured in both crystalline and noncrystalline arrangements. When slowly mixed with water, the non crystalline structures of corn starch absorb most of the water. When you smack or stir it rapidly, you increase the temperature and pressure on the mixture which causes more non crystalline structures to form. These new noncrystalline structures absorb more water and the mixture becomes thicker:hence the appearance of a solid. When you discontinue the pressure, the number of noncrystalline structures decrease and water is released, creating the 'soupy' mixture.

GUAR GUM SLIME
Put 1/3 cup warm water into a paper cup. Use a stirring stick and add 1/4 teaspoon guar gum into the water. Stir until mixed and the guar gum is dissolved. Optional:add 2-5 drops of food color. Mix thoroughly. While stirring, add about 2 tablespoons 4% borax solution to the guar gum mixture. Once the mixture has gelled, remove the Slime from the cup and knead it in your hands. Place the Slime in a zipper-type plastic bag to prevent it from drying out. A few drops of Lysol can be added to the Slime to minimize the formation of mold and extend the lifetime of the Slime. You can get guar gum from Flinn Scientific.

POLYVINYL ALCOHOL SLIME
Put 2 tablespoons 4% polyvinyl alcohol solution into a paper cup. Add 2-3drops of food color. Mix Pour in 4% borax solution into the cup of polyvinyl alcohol solution. Stir constantly while the borax solution is being added. Once the gel has formed, remove it from the cup and knead it in your hands. Place the Slime in a zipper-type plastic bag to prevent it from drying out. A few drops of Lysol can be added to the Slime to minimize the formation of mold and extend the lifetime of the Slime.

SLIME OLYMPICS
Experiment with each of the Slimes by squeezing it; forming it into a ball and throwing it onto a tile or linoleum floor; by pulling I gently and then quickly; and by pressing the putty on top of your name written with a water-solubnle, felt-tip marker. Note: Differences: The Guar Gum Slime is less viscous (more runny) and can be stretched further before breaking than the Polyvinyl Alcohol Slime. Similarities: Both slimes are clear and colorless (if food color is not added), can be molded into different shapes, will flow from a funnel over a period of time, will bounce (to a certain degree), and will become flat if left sitting on a flat surface.

The following recipes are Contributor, Paula Lee pmlee@ties.k12.mn.us:
LOTION PLAYDOUGH
1 cup flour
1T vegetable oil
2T hand lotion
1/2cup salt
2 t. cream of tartar
1 c water
food coloring
Mix. For kids crafts.

FUN DOUGH
1 cup corn starch
1 1/2 cup baking soda
food coloring
water
Add water to dry ingredients to desired texture and consistency. Color with food coloring.