More ideas
PPE fashion show
Mock accident investigation - see who comes up with more root causes
Best checklist contest (with time limit)
Hazard scavenger hunt
Safety slogan contest
Forklift "rodeo"
Contests/games (i.e. Jeopardy) focusing on site-specific hazards and solutions
Establish an accident investigation toolkit including things needed to investigate accidents or near misses (forms, disposable camera, tape measure, etc.)