Six Glass Shuffle
There are six glasses in a row. The first three (1, 2 and 3) are full of juice; the second three (4, 5 and 6) are empty. By moving only one glass, can you arrange them so, empty and full glasses alternate?
Consider the word
It does not have to mean just moving the glass from one location to another
You can do something with the glass you move!
Pick up (move) glass 2, pour it's contents into glass 5, and return it to where it was.