Hi,
I sometimes get outside speakers into my lessons in school. The pupils tend to respond best to activities where they get given a pack of pictures/words in a plastic envelope and get into small groups. There's loads you could do, such as
• Get them to rank different types of people into who looks like they'd self harm and who wouldn't to encourage them to break stereotypes down.
• You could also get them to find links between 2,3 or more of the pictures and words and to explain why they've linked what they have.
• You could give them agnony aunt style situations and they have to come up with what they think the responses would be from different points of view, such as a friend, parent, teacher, GP, someone in their year group.
Hope I've helped. My brains not working as well as it should this time of night!