NNFN2023 Ideas: Oobleck

Goop is great fun to make and explore- and offers plenty to discuss as it doesn’t behave as you think it should! Is it solid? Is it liquid? This substance is known as Oobleck and gets its unusual name from a Dr Seuss story, Bartholomew and the Oobleck. It is a non-Newtonian fluid, meaning it doesn’t follow Newton’s law of viscosity. Non-Newtonian fluids become runnier or thicker when the force on them changes and children are enthralled by how this substance can be both liquid and solid!

To make the goop, you need cornflour, water and food colouring in whatever colours you fancy! The measurements are not exact as it needs to be mixed to the right consistency and it is a good idea to protect surfaces and clothing as much as possible- I speak from experience!

Mix the water and food colouring into the cornflour, until it reaches a thick consistency. If you make smaller batches in different colours, children can experiment with mixing these and observing what happens.

Another fun way to explore oobleck is to freeze it. Put the mixture in an ice cube tray or other mould, then put it in the freezer for several hours. Things like flower petals can be added to the mixture to create interest. It will thaw slowly whilst being played with, offering more opportunities for scientific discussions!

Although I have never tried this, I have been reliably informed by colleagues that fluffy oobleck can be created by putting some cornflour in a bowl and adding shaving foam on top. Food colouring can be added if required and everything needs to be mixed, adding more cornflour or shaving foam until the desired consistency has been achieved.

Enjoy feeling the texture and discussing the properties of the goop whilst making patterns and shapes in the mixture. Great fun for everyone!