Or you're painting a bullseye on your back. Increasing your profile is usually bad tactics- asking what you are allowed to have on campus usually makes people nervous in my experience, and that was on a college campus not a middle school. These policies are intentionally written with maximum amount of space open to the schools; the student who runs afoul of them accidentally is generally hosed.

Erring on the side of caution rarely harms. And scrounging up things like a moderately sharp or better edge is usually pretty easy.