If I finish all of the physics a lesson or two before the end of term, I like to use those spare lessons to do something fun. For the last 12 years I have done a boys vs girls engineering challenge and the girls nearly always win. Here is why...
So, my experience of this is normally allowing 5 or so classes do this activity in any given year, always with the same set up and always with me observing just how it goes. In total I must now have observed the experiment about 60 times.
To be clear I am all for students choosing their own teams and such and I am aware of the false dichotomy of the situation. But generally due to sports, boarding houses etc my crew are quite used to boys as one gang and girls as another.
The activity is bridge building. Two tables are set apart and each team must bridge the gap using only paper, string and 4 clamp stands. The bridge must have a roadway and each will be tested to destruction at the end with weights.
So, I split the class - girls vs boys. The rules are clear. They can't interfere with each other's bridges and they can't test their own bridge. They have about 45 minutes to build something. Let me tell you what then normally happens...