Ask if the gears any good
In my experience

deals like that outside are usualy for cannabis if its involving teenagers but maybe these days the kids are just not giving a damn and getting hard drugs out in public. Eitherway,its illegal and from my experience

if you have these kids in your area doing that sort of stuff they will also be doing other things like spraypainting the inside and outside of any building they can get access to ,steal bikes that are chained up or any other valuable property they can get their hands on to pay for their crappy little 10-20 bags of weed.
Long time ago when i was abit of a dodgy geezer

doing some stuff i shouldnt have been i ended up starting what the police described in the papers as organised crime......it was just the little idiots i went to school with who were stealing sat-navs,bikes,robbing eachother out on the streets and all sorts of mayhem but it was on such a large scale that they reconed it was some sort of gang/criminal enterprise(it was just a bunch of numptys wanting money for green).The landlord and neighbours realised what i was up to and kicked me out of my first flat i lived on my own in for being the idiot that i was back then(this is just over 10 years ago and im lucky i didnt get sent to prison and learned my lessons through other means...)
What you described reminds me of how that all started in my area back in the day....im ashamed to admit this but from first hand experience call the police on them,you'll be doing them all a favour in the long run. Might give them the kick up the jacksy they need to get their life in order.