| Every time we ask a “hands up” question, we exclude the four-fifths of the class who don’t put up their hands. And if six raise their hands and we choose only one to answer then we exclude five more. It’s an unintended consequence, of course, but it goes some way towards explaining why so many children get to “sleep” through lessons, letting others take the strain. Many schools have banned hands-up but most continue with the tried (and unproven) method against all the evidence that it harms concentration, disappoints and demoralises. | 
