Being at an event surounded by people you don't know can be intimidating at the best of times! Here are some tips and ideas of activities you could run at the start of the jam to help people get to know each other, and to get into teams.
Have an informal social or pre party with drinks and dinner on the Thursday night (or even the Friday night!).
Before you play the keynote, get people to introduce themselves to the people to the left and right of them.
Get everyone to stand up and give their name, where they have come from and 3 words about themselves.
Randomly divide people into groups of 5 strangers. Get them to introduce themselves, and say what their favorate games are, what their expectations for the weekend are inside of these small groups.
Tower building out of materials
idea for Icebreaker -> draw a 4 panel comic strip about your life, and then swap it with someone to explain // Use a ball to find who will next speak
Line your jammers up in 2 lines
Have the lines face one another
Starting with one line (we use the right side), have all the jammers in that line pitch themselves or their ideas for 15-30 seconds
Call "Switch" and have the other line of jammers pitch themselves for 15-30 seconds.
Skill/Interest stickers ?