It keeps them alert and active, instead of passive and receptive; it makes them more useful, more capable
Entirely because they are able to make neural connections which solidify and anchor learning in long-term memory. Student attention spans and interest have skyrocketed in classrooms with coding, robotics, music production, invention and innovation to solve a genuine problem in our society or world. I remember not wanting to teach my students without providing these opportunities because I felt I was doing such a disservice to their futures. Why do we allow non-relevant learning to continue? When will students need derivatives in their lives? When will they need factoring on a daily basis? They shouldn't be forced to learn them unless they are part of the solution to the problems they are faced or challenged with.