NEED HELP IMMEDIATELY: How did Mr.Hadley's remarks reflect a complete lack of understanding of the situation at Devon and the war in general?

I'm kind of guessing which remark you mean as you were not specific. Mr. Hadley belittles the boys for using sewing machines (to make uniforms) instead of marching or performing "manly" activities. He really is clueless that these are still kids who have no idea of war. These kids are doing what they can to support the war effort without concern for outdated gender roles.

“You boys look fine, fine,” he said in his full and cordial voice, “better I would say than those doughboys—G.I.’s—I saw marching in. And how about their artillery! Sewing machines!” ch 13