I really like the link that Christy Lee gave pointing out that sometimes the Rosary as a necklace is being used as a sign of gang affiliation....
"wearing rosary beads around the neck has become a gang-related badge of identification."
We had our local police department gang taskforce come and talk to the teachers and staff at the middle school we work in, and this is one thing they REALLY pointed out..... so, we added that to our dress code as not being allowed.
It just took a few weeks for the kids to understand we were serious, and wouldn't allow people to wear rosaries as a necklace.
If they want to wear it, it must be under their clothing, and not visible at any point, even a few beads at the top.
We are really trying to crack down on any kind of gang affiliation at our local middle schools..... trying to keep the schools a safe place for the kids. And, yes, even in middle school the kids are being recruited for gangs!