When I taught 3rd grade
I had a problem with teamwork and cooperation so I had the class get in groups of two. I gave each team a box, scissors, wrapping paper, ribbon, and card. I put a paperbag on their dominant hand so they would have to work together to wrap the present and write the card. I then had another teacher come in and choose the best wrapped present. The team that won, earned a free night without homework. It was a long process te first time but well worth it in the end.
Then I followed up with what are some things in life that you have to cooperate work together? What happends when you don't. What are some examples of how we as a class can be a team and work together and why will it make us a better class?
The kids really loved it. Then in a month, I did the project again. The kids cut their time by about 60% and learned that working together helps everyone.