Bausch & Lomb 3 1/4" 2x round magnifier

I am a sixth grade teacher in Claremont, California. I have up to $500 to spend on science supplies. I want every student of mine to have a hand lens to be able to use for various science and outdoor education projects. I have 34 students. What lens would you think would be the best for my class. I would probably want a couple of extra ones and would like some kind of protection for lenses if that is possible and not too much more expensive. Thanks. I was looking and the B&L 3 1/4 inch model. Would that be a good one? Do they come with pouches?

Hi

Try the Bausch & Lomb 5x Aspheric Magnifier if you are looking for a handheld with a case or a pocket magnifier with attached case, such as the Bausch & Lomb Folding Pocket Magnifier.