Divide the workshop participants into any number of smaller group in a randomised fashion. It is a fun way to do it.
Form heterogeneous teams / avoid close ties to work together to foster group thinking
No special forces needed from the facilitator. It is enough if you are able to check numbers from 1 to 31 are in ascending order.
Don't tell the purpose of the exercise upfront. Tell them it is going to be an energizer, requiring both their mental and physical resources.
Ask all participants to line up according to the day of their birthday from 1 to 31.
If one day occurs more than once, the month will define the order. If even the month matches, then the year will tell. If there are people born on the exact same day, it is time to celebrate. (never happened to me).
Once the group thinks they are done, go run a check round. Ask them to tell their days one by one, in ascending order. Correct any mistakes if needed.
Ask the group to listen carefully. You are going to tell them a number. You are going to tell them only once, so better listen carefully.
Now, start to count from 1 to x (x = the number of smaller teams you would like to divide the group), pointing one person in the line at a time, then move to the next. Continue till you get to the last person in line. Say you would like to divide a 12 persons group into 3 teams of 4s. You count 1-2-3, three times pointing one person at a time.
Now ask the group to tell back the number you just told them one-by-one. Ask them to do it again, even faster. By this time they will know what was the purpose of the exercise.
Still, make it clear by asking them to divide into x groups according to the number they just told. Whoever got the number 1 will form team 1. People with number 2 will be team 2. And so on ...
Check if the randomised teams are really heterogeneous. Course correct if necessary.
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