To help others succeed simultaneously with your success.
one on one (two) Can be done with groups of any size by making subgroups of two.
Lunch/Dinner, A stick and a thread for strengthening the hand joints of the participants.
Tell the participants to eat food. For some it'll be impossible and for others who'll be thinking out of the box, they'll serve their partners, thus, eating the food.
Any creative problem solving debrief would be applicable here.
Don't make pairs of two, rather make them solve this problem by themselves.