Exploratorium
Exploratorium: Salt Volcano
By making oil float on water--with the help of other ingredients--students can create a lava-lite effect.
Science is Fun
Science Is Fun: Layered Liquids
An investigation into what properties liquids have that enable them to sit in separate layers in a container.
Other
The Science House: Red, White, and Blue Ii
This colorful demonstration illustrates the rule, "likes dissolve likes," by combining three, immiscible liquids to create a density column." Teacher notes provide background information.