I recently learned that tennis shoes thrown over the wires are a sign of gang activity and if shoes are on the roof of a home, it means drugs can be purchased there. I pass by seven or eight sets of shoes, and see four places with shoes on a roof in the neighborhood on the way to my school. I've been looking since someone told me about this in the town where I live and in other neighborhoods in the town where I teach and I've not seen these signs (which is good I guess). I knew the area was very poor, has drive by shootings, and many of my kids' parents are heavily involved in gangs, but it just surprised me to see such an obvious sign of trouble. What other signs have I missed?