Hmm, A name and shame policy, where pupils/staff can anonymously (but obviously cite reasons), name and shame their school for failing on homophobic bullying.

For example, vandalism at my school is usually corrected very quickly, within a week. One guy got expelled for painting on the wall.
However, someone used paint remover or something, not completely obvious, but definitely visible. They wrote homophobic language and the name of the person they were bullying on a yellow door in the school. This has been there as long as I remember, and never (in my knowledge) tried to be repaired.

Another example could be a pupil reporting homophobic bullying but getting no support from the school.