Your mission

A mystery object is sealed inside the box. You cannot open it, peek inside, or poke a hole in it.

All you can do is ask the box yes or no questions and run a few tests. Use what you learn to cross out objects on your shelf.

Then make one final guess. Say what the object is, what it is made of, and how long it is.

The best detectives do not ask the most questions. They ask the smartest ones.

Detective tips

  • Ask big questions first. A big question crosses out many objects, no matter what the answer is.
  • Look-alikes hide in the small details. Check the material and the size.
  • A test uses up a question too. Save tests for when a yes or no will not help.
  • Talk before you tap. Your whole team should agree on each question.

Your level

Every level adds more objects and more look-alikes to your shelf.

My badges

Badges are saved on this Chromebook.

    Teacher note

    How it works. There is no AI on this page. Each of the 100 objects has a fact sheet, and every answer comes from that sheet, so the box always answers the same way.

    Each box. A shelf shows the objects that could be inside. Students get 8 questions or tests, then one final guess with three parts. A box counts as solved when they name the object. They earn one star for each part they get right.

    LevelObjects on shelfLook-alikesBoxes to move up
    1 Rookie1013
    2 Sleuth1423
    3 Detective1834
    4 Inspector2244
    5 Master285Keeps going

    Look-alikes are objects that share most of their facts with the hidden one, like three kinds of spoon. At level 5 the box also stops telling students how many objects each question ruled out.

    Wrong guesses. There is no second try. The box opens, shows the answer and its fact sheet, and a new box with a different object arrives. An object will not come back until the student has seen all 100.

    Good to know. Length means the longest side, in inches. The material called clay or stone covers mugs, plates, vases, bricks, and rocks. The magnet only sticks to iron and steel, so the penny, key, and ring do not stick. The metal spoon and fork are steel in this game, so they do.

    Team play. This works best with two or three students sharing one Chromebook. Ask teams to agree on each question before they tap, and to say out loud which objects an answer crosses out.

    Try it for real. Put a real object in a shoebox and let one student be the box while the class asks the same kinds of questions.

    Saving. Levels and badges are saved on this Chromebook only. They do not follow a student to another device.