I know some people that do drugs and smoke crystal meth?

Well i dont really know them, i know OF them. they are just an aquantance and they go to a different school thats very close to my school. Girl A drinks, smokes weed;; and Girl B smokes crystal meth and she looks really ugly and old but shes only 14?? Should i tell someone.....? And Girl A has a little sister thats like only 13 and smokes cigarretes... Its not really any of my business but seriously?

: http://alcoholdrugstreatment.info/i-know-some-people-that-do-drugs-and-smoke-crystal-meth