One of the best things about science from a child's point of view is how it allows them to get their hands dirty, while still having fun and maybe even learning something new along the way. An elementary discussion of basic chemicals or even a simple description of polymers can end in this fun, hands-on project. Whether you call it slime, gak or goop, early lab work of this variety can pave the way for a positive attitude towards the sciences in general and can help foster an early interest in chemistry.
Spread sheets of old newspaper across a flat surface. Place your bowl in the center of the papers.
Add 1/2 a cup of glue and 1/2 a cup of water to the bowl. Stir with a wooden spoon or craft stick until well blended.
Fold two to five drops of food coloring into the glue mixture, if desired. Some favorite gak colors are blue, orange and greenish-yellow.
Combine one tablespoon of borax and one cup of hot water in a separate cup or jar. Stir or shake vigorously until all the borax is dissolved.
Add an additional ½ teaspoon of borax to the solution and stir until the powder dissolves. Repeat this step until the water won't absorb any more borax. This solution is now saturated.
Pour two tablespoons of borax mixture into the bowl with the water and the glue. Quickly whip the borax into the glue, stirring until you create a slimy ball of goop. If your gak is too sticky, add a bit more borax and blend it in, kneading the slime with your hands if necessary.
Repeat the procedure for each child present. Alternatively, children can mix the glue and water at their individual stations and you can distribute the borax solution, allowing them to mix it. The resulting gak globs can be stored in plastic zipper bags indefinitely. If properly stored, the slime will not dry out for several weeks. If the goop does dry slightly, it can be restored by adding a slight amount of water. Eventually, even with the most diligent efforts, the goop will dry up completely and it will have to be discarded.
Food coloring can stain both clothing and skin, so wear protective aprons to cover your clothes and disposable gloves when first handling tinted gak. With time, it can be safely handled without worry of color transfer.
Feel free experiment with this mixture, as there are no set rules for the quantities of each ingredient. The formula above is a rough guideline only and various factors such as the brand of school glue, the temperature of the water, and the relative humidity can affect the overall outcome.
Borax is a common laundry aid and can be found in most department or grocery stores near the detergents and bottles of bleach.