The Missing Question
Three empty places and no numbers at all — before anything is said, the class decides what could be asked.
About this tool
Three empty places on a stand, and nothing else. No numbers, no sentence, no picture of what happened — and no question, because the question is the thing the class is going to make. At the start nothing has been said, so there is nothing yet to answer, and that is the point: the only job at the opening of the routine is to decide what could be asked.
From there each press adds exactly one fact. First how the three places go together — a linkage is drawn, and still not a single number. Then one number. Then the other. The apparatus only ever gains; nothing is covered and nothing is taken away, so between presses the class can say what it knows and what it still does not.
The place left unsaid is the question. Once both other numbers have been told, the class counts the missing amount out loud on a strip below the stand — one counter at a time, into a row of wells whose size never changes. The answer arrives because the class counted it, never because the tool printed it.
The same three places sit in three relations: something happened, two make one, or one has more than the other. Change the arrangement and the two told numbers stay where they still fit — and the answer is different. Nothing here is scored, timed or ranked, and no question a child asks is ever judged. This routine is research-based, not evidence-based. The whole apparatus is free; a Teacher plan adds the printed sheet.
How to use it in class
- Set up the situation before the lesson: choose how the three go together, how far the numbers reach, and which place the class will have to work out. Then show the empty stand and say what is happening — without a single number.
- Take the questions first. "Nobody has asked you anything — what could we ask?" Every question counts and none is marked. This is half the routine, and it only works while nothing is known.
- Show how the three go together, then tell them one number. Stop there and ask the two questions that matter: what do we know now, and what do we still not? Then tell them the second number — now the question has one answer.
- Count what is missing together, out loud, as the counters arrive one at a time. Then keep the same two numbers and change the arrangement: ask whether the answer changes.
Classroom ideas
- A three-minute opener: one empty stand, three questions from the class, and only then the first number.
- With one number told, ask the hard question — what do we know, and what do we still not? That is the moment a fact becomes distinguishable from an answer.
- Tell the same story through all three arrangements. The two told numbers stay put and the missing one changes, so the class discovers that the answer depends on how the three are related, not only on the numbers.