Boys thrived in the rules-based school environment of days gone by where discipline was firm and consistent and every action had a clearly-defined consequence.
Four decades ago, teachers favoured a teacher-centric approach to learning. Students were required to memorise facts and subjects like maths and science were taught by drilling. However, in recent years, schools have adopted a more progressive style of discovery learning that better suits female students.
Discovery learning requires students to be creative and engage their naturally curious minds to explore the world around them. Rather than impart knowledge and facts, teachers are expected to guide students through the learning process, building their self-esteem and teaching them how to learn from both their teachers and their peers, instead of what to learn. In modern classrooms, discovery learning takes many forms. One form, for example, is to have students work in small groups of 5-10 students. Rather than sitting in rows and working individually, students have to work collaboratively on problems and tasks, as they would in a modern workplace. This clearly benefits girls, who are better at working cooperatively and are more likely to stay focused on the task and avoid distractions. Male learners are usually less mature, more impulsive, and more easily distracted. As a result, they benefit more from older methods of teaching, which were more structured and had clearer expectations.
A study in 1990 found that female learners, when learning mathematics, performed much better when a rote learning approach was employed. This would go against the argument that females tend to do better in environments where students are engaged in discovery learning. In the same study, males performed better when they took an autonomous approach to learning maths.  Admittedly, the study did find that when it came to problem-solving, rather than learning, females performed better in groups, while males performed better solving problems individually. However, the argument that old rote learning styles of memorization and recall benefitted boys does not stand. It becomes difficult to say with any degree of certainty that one method of teaching favours one gender. The reality is far more complex with individual learners sometimes favouring more auditory forms of teaching, others more tactile forms and others more visual forms. The school system is not designed to benefit one specific gender, but one group of learners. In schools where discovery learning is encouraged, more social and auditory learners might excel. In schools where other teaching techniques are adopted, visual learners or tactile learners may flourish. The school system will always benefit one segment of learners, but it is not possible to draw clear distinctions based on gender.
[P1] Modern teachers have adopted a more student-centric approach to teaching. [P2] This better suits female learning styles. [P3] Therefore, the modern school system benefits girls more than boys.
[Rejecting P2] We cannot apply blanket statements that assume one teaching methods benefits one specific gender. Every learner is different and some teaching methods benefit some learners, while others benefit other learners, but these demarkations cannot be made along gender lines.