[x2495iiii]

If you click the sky on your world, the world itself will be selected. While the world is selected, click the functions tab to see the nice selection of functions included with Alice. Two of those are random number and sin [a]. My idea was to have the fish move back and forth, while at the same time moving up and down in a sin curve to simulate a wavy pattern (this is actually one of the assignments in the textbook, see if you can find it for more info), then adding a random number in there somewhere to make it look less mechanical (where you add it depends on your taste, you could add it in the duration to make him move faster or slower randomly, you could add it in the back and forth motion to make it look less like he's just swimming the same bounding path over and over, etc.)