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Make Your Own Slime!


  • Borax powder
  • cup
  • spoon
  • 8 oz. bottle of gel glue
  • food coloring (optional)
  • measuring cup


  • Pour the glue into a mixing bowl and fill the bottle with water. Shake the bottle to try to get the glue that stuck to the bottle to mix in, and then pour the water into the bowl with the glue. Stir well. Note: if you can only find the 5 oz. size bottle of glue, that's fine, just use less of the borax mixture later.
  • Add food coloring to glue/water mixture, if you want the slime a particular color. Just a drop or two will do the job. Gel food coloring bottles come in neon, which makes for some cool slime.
  • Measure ½ cup warm water, pour into a cup, and add a teaspoon of borax powder. Stir it up, but don't panic if the borax doesn't all dissolve. It's okay if there is still borax on the bottom of the cup.
  • Stir the glue/water mixture, and slowly pour the borax in. You don't need to add all of it; the more borax you add, the thicker the slime. If you add enough borax mixture, you will get almost a putty-like texture. If you want slimy slime, you won't need all of the borax mixture.
  • Once you feel it turning into slime, you can use your hands instead of the spoon.
  • You can store this in a ziplock baggie or an airtight container.


  • Don't eat this!
  • Be careful with the borax; it's caustic to skin.
  • You've just created a polymer, which is a material that is like both a solid and a liquid at the same time! It's because the molecules chain themselves together and can stretch and bend.
  • This is also called a non-Newtonian fluid because Newton said that it was temperature that determined the viscosity (liquidness) of a liquid, but the viscosity of this is changed by other factors (as you saw as you added more borax solution).
  • You can make ink imprint into your slime by laying it on newspaper or other water-based ink.

Mensa for Kids Activity Plans are designed to simultaneously entertain and challenge gifted youth in their time outside of the school setting; however, the activities may be easily shared and enjoyed by older people as well. Programs may be scaled up or down depending on number of attendees, desired level of complexity, etc. Sample materials are included with most plans. This activity plan was developed by Lisa Van Gemert, M.Ed.T., the Mensa Foundation’s former Gifted Children Specialist. If you have questions or comments about these programs, please email our Gifted Youth Programs Manager.