Laser for low tech communication- testing laser power

Hi-
I use Class II lasers (>1 mW) to make low tech communication aids for people who are paralyzed and can't speak. (The laser attaches to a pair of glasses, and allows a person to point to letters and words on a paper communication board using head movement.)

I'm looking for an inexpensive way to test the class/power on about 40 laser modules... (I got these a long time ago, and I want to double check to make sure that these are >1mW).

I appreciate any suggestions- Thanks!