Warning : DO try this at home as it’s cheap, non-toxic and excellent fun. Starch (for example cornstarch) suspended in water is sometimes called Oobleck after a Dr. Seuss book (Bartholomew and the Oobleck) and is an example of a non-Newtonian fluid.
Temperature can cause some materials to change state; heat water and it becomes a gas (steam), chill it and it becomes ice (solid). Pressure can also change a material’s state and with Oobleck a change in pressure can change it’s properties. Pressing on it increases it’s viscosity and makes it thicker. Add beats to the mix and you have a dancing Oobleck monster.
There are plenty of videos of Oobleck on Youtube but this is my favourite because the music matches the movement so well.