Slime!

It's a very simple activity. Pour a cup or so of cornstarch into a bowl. Slowly drizzle in water, stirring as you go. It will be very stiff and lumpy at first, and will become more liquid as you pour in more water. Tip: Stir slowly. The oddity (and the appeal!!) of this stuff is the faster you stir, the more solid it becomes. Green food colouring is optional, of course.

When it's the consistency you want (we went for cream), you will find that if you put your finger in slooowly, it feels just like water. (Or cream.)

But if you lift your finger out, it will ooze and drip like... slime!

Slime...

Drip!

We all loved it.

The science lesson? It's an isotropic liquid: when it's agitated, it becomes more solid. So, reach in and quickly clutch a handful, and you can lift it out like crumbling pie dough. Within a second or two, though, if you hold your hand still, it will revert back to liquid and oooooze out between your fingers. Stir it quickly, and it will mound up against your finger or spoon. Stop stirring, and... back to innocuous liquid.

Nora was particularly fascinated, and stayed at the table long after the others had become bored. Poke, stir, lift. Solid, liquid, ooze. Very Zen, our Nora. :-)