I successfully used “instance” pop to creat instance objects in pop environment. Can any one show me how I can rotate them randomly with some constant speed? I think the “rotate” pop should help but I just did not use it correctly.

torque pop

Correction: Over-read your post. Torque will invariably add noise to your rotations making them turn at varying speeds.

You could use the rotation pop if its important to maintain constant speed
use a simple expression to control the speed, something like $F*20 in the angle field, and some random expression in the axis fields should give you what you want

It works! Thanks Talkien!