Onegaishimasu, I would like to know how other dojos are handling age differences in class, especially teenagers who pair up with older folks and look at it as a challenge to strut their stuff.
At my old dojo, we had a sandan who was older, but strong as an ox from working in construction. We let the teenagers play with him until they learned some manners. Which didn't usually take more than a class or two.
More generally, if your senior students can't handle frisky teenagers, there's a problem with your training that needs to be fixed.