But Jonty30 didn’t blame anyone for this outcome, so the information is worthless.
I think the simple answer, which has been alluded to here, is that boys require a more active education than girls. Girls are fine with the passive method of teaching that is used today, whereas boys need a more active method. For boys, running contests or being able to jump up and yell out the answer, or have to defend themselves in a debate, etc, is needed for them to be engaged.
That’s why many of them are checking out, a lack of interest.
Ding! Ding! Ding! You win. Best post of the day.