Upload & Sell: On
I'm not an expert, but I have noticed some things. You'll know right away whether there is going to be a problem or not. You'll see the reflection off the lenses from your modeling lamp or even the house lights right away. It has nothing to do with the thickness of the glass but more to do with the curvature and quality of the glass itself. Sport goggles are the worst. They have nearly a 180° degree angle of refraction.
But, getting to the question. You really can't ask the kid. You have to ask the parent paying the check. If I see zero refraction of light. I just shoot it. I know I will be okay. If I see some potential problems, I will start widening out the lights and all the way to 180° if I need to. Since the softbox causes the greatest amount of light reflection, you may have to angle them away from the softbox a bit. There is no set rule regarding what to do. All lenses reflect differently and you have to play with it. Also, be advised that as you widen the lights, you may have to open up the aperture to eliminate any effects of raccoon eyes.
If all else fails, you may have to ask the parent to have the child remove the glasses. This has never happened though... I will usually get it right after playing with the lights. Again, sports goggles are usually the worst and you may have to deal even just a little bit of reflection in the corners. It is what it is.
From a management standpoint though... my poser knows that all kids with glasses on a team are shot last. You don't want to have to move the lights back and forth. Wait till the end because once you move the lights, it will be good to go for the others. Plus, the other kids have already been shot and been moved to the team staging area and the kids with glasses aren't being looked at by the others.
A couple of things worth mentioning. Always ask kids with glasses to push the frames all the way into the face. You may nail the light only to realize that the glasses are on the lower bridge of the nose and the top part of the frame, is blocking the eye. If you need to remove glasses from a kid's face, be conscious of any nose and cheek divots left behind by the glasses. The kids may need to rub that out or it may need to be PS'd out depending. Another reason why it may be better to keep the glasses on the face whenever possible.
How is this longwinded response for the short question you asked Frank?