Usually, situations aren’t as they appear on the surface. If half or more of students in a classroom aren’t paying attention, it isn’t necessarily that the teacher is lacking in skill. It is also not necessarily that the kids are naughty. There is probably something else going on.
All children fall somewhere on a spectrum from left-brained dominant to right-brained dominant in how their brains are wired to learn. It will benefit both children and teachers to understand the child’s unique wiring.