Put a whole bunch of packets of clear gelatin into a bowl of boiling hot water. Dissolve. Put about 3 or 4 times the amount of gelatin that you'd normally use to just make it gel. You want it very firmly gelled.Let the bowl cool and then put in the refrigerator to really gel well - the bowl is the mold.
Take it out and set it in some warm water - just long enough to loosen it and then dump the bowl-shaped mound over onto a plate.
NOW - put out bowls of tempura paint and plastic eyedroppers - suck up paint into the eye dropper, insert the eye dropper very gently into the mold - stick it way in. Gently squeeze the paint out of the eye dropper. Pulling the eye dropper out as you squeeze is especially cool.
Keep doing it with different colors - all over the molded gelatin. It looks so beautiful as the colors spread and mix. Very fun. We used to make several molds at a time.
My next favorite thing:
Put milk on a plate - you can use a pie pan or a cake pan - but something with a large flat surface, like a plate, but will hold liquid. Put enough milk so that the bottom of the container is covered.
Put drops of food coloring here and there, all over the milk.
Put a drop of dishwashing soap onto the surface - into the coloring. Watch what happens.
ICE!
Ice is a good bathtub toy. Some people suggested freezing a little toy inside ice, like in a popsicle mold. Just ice can be fun, frozen in a bundt pan or some kind of mold. Jello molds (large or small)--we have a copper fish mold and a fish made of ice is a bathtub toy you don't have to clean up after. Regular ice cubes can be fun, too.
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