Yesterday I gave my PD5 workshop with my team. Our workshop was called 'HES Challenge Day', after the MTV program. Our aim was to get everybody to share themselves more with our class, and to understand each other more.
We did funny warm up activities, a game called 'Cross the line' and one called 'If you really knew me'. It was very beneficial, as even if people don't talk about their most intimate secrets, you always find out things that you did not yet know even if it is as random as past jobs or hobbies.
I enjoyed myself, and I would encourage others to organize a similar event for their class as well. It might be nice to do so earlier in the year, as most people in my class are leaving for exchange soon and we will not be able to reap the benefits of our Challenge Day.
It could also help your class in improving cooperation during the teamwork activities.