“I only discover misconceptions when marking”

Most of the checks a lesson offers you measure confidence, and confidence is a poor guide to understanding. You ask whether everyone is following and get nods, partly because saying no in front of the class costs something, and partly because a misconception feels like understanding from the inside. The answers you hear out loud come from volunteers, the students least likely to be wrong. Nobody is hiding anything on purpose. Marking is simply the first time every student's actual thinking is in front of you at once.

The delay persists because the lesson feels fine while it is happening. "Got it?" takes five seconds and nearly always returns good news. Checking properly feels like losing minutes you cannot spare. By the time the books say otherwise, the class has moved on and the mistake has had days of practice. The techniques below move the discovery into the lesson itself, in three ways: some replace the reassuring check with questions a misunderstanding cannot slip past, some send you to the work while it is still being written, and one makes it safer for students to show you they are lost.