I do agree there's a disparity between educational outcomes in men and women - but I don't think you can immediately draw your conclusion:

Baked into it is the assumption that current education models fit both genders equally. Boys respond better to active learning and competitive techniques than the more passive techniques used currently. (Could we just as easily draw the opposite conclusion if our current educational culture was geared towards boys?)

Another thing to consider is the various programs that incentivise/enable girls to get into various subjects (in my n=1 experience I had much fewer programs (programming, robotics, maths, etc.) to join despite being already very interested and strong in those subjects).

By comparing age groups directly we are also not controlling for the fact girls mature faster making them better students earlier in life. We are also not considering tail effects of a normal distribution: e.g. top 5% of all students are male, but majority of students in the top 50% are female.

Maybe the solution is to segregate schools on gender, but that doesn't immediately equate to boys crashing and girls excelling.

I agree and I don't think gender-segregated schooling is a wise idea. But the argument is Kryptonite to those who favor school segregation because they realize that they more likely than not would end up in the loser group. Works wonders on race baiters too, who has to come up with "reasons" why girls beating boys is the result of "unfairness" while whites beating blacks is "natural".