Oobleck is cornstarch and water that when mixed together can act like a solid and a liquid.
At times, it may seem like a solid or a liquid but it acts differently than a normal solid or liquid. Making oobleck is a great science experiment to show how changes in pressure can change the properties of some materials. Sort of like how temperature changes the properties of water. Cold or freezing temperatures turns water into ice. Whereas warm temperatures melts ice and turns it into a liquid.
Warning! If you’re trying this at home make sure you’re careful not to get in on the carpet as it’s difficult to clean (we found out the hard way) and if you’re adding any food colouring to it, it may stain”