Making Slime or Goo ( oobleck )

This is a nice and simple experiment, but oobleck is  quite messy, so I’d recommend doing it outside. 


What you need

  • A big bowl
  • cornflour
  • water
  • food colouring (optional )

What to do

  • Fill a cup with cornflour and add to the bowl
  • Add water very slowly mixing with your hands all the time, until you get a sticky, slimy goo.
  • If you want to make it coloured add some food colouring, be careful this can stain skin and clothes.
  • Play with the slime and see how it behaves. Can you make it into a ball? and what happens if you throw it onto the floor?



The Science Bit

Did you notice that if you make a ball with the slime it is solid, but if you drop it on the floor it turns liquid again? The slime is a non – Newtonian fluid as it doesn’t flow like liquids normally do.
The slime is made up of molecules arranged in long chains. When the chains are stretched the liquid will flow, but when you force them together they stick together to form a solid.

There are 15 comments

  1. Ross Mannell

    I always loved this activity. A favourite was rolling a ball in the hands then handing it to a child and watching it collapse. I would then ask what they thought had happened. Their responses could be very creative.

  2. Lisa Hagg

    This is a big hit with my two girls (Emily 4 & Phoebe 2) and features in our Little Explorer classes for toddlers/preschoolers too and it is an activity that is always approached with curiosity, awe and amazement! Loving the picture too, this is a good activity around Halloween time especially if using green colouring. To avoid staining, particularly for younger children, we use waterbased paint to colour the ‘goo’. Thanks Lisa

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