Team competes to collect the most cones in a minefield, without entering it, using ropes & short poles
Rope the length of the hall, 10 of 1 metre lengths of string, 10 of 60cm poles, chairs to form a cordon, cones (at least one per team)
Create a minefield boundary using chairs, marks on the ground, or something similar - no member of any team is allowed within this area. Instruct one team member in the rules & allow them to brief their team. Team must lift the cone, not drag it, to remove it from the minefield & they will get a point for each cone rescued.