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Teams learn by testing early.

Run the marshmallow challenge with every test logged: teams build a spaghetti tower against the clock, a teammate logs each time the marshmallow goes on top, and the room's own record shows when each team first tested. Predictions are sealed before the build, so the class can also compare its plans with what it built.

The marshmallow challenge

A practice run with fictional students. No real classroom or join code is created.

Try an answer on the phone. Lead the lesson from the screen.

On their phone

You are presenting

Setting up the room…

  • Your team—

    The marshmallow challenge

    Teams of four get twenty sticks of spaghetti, a metre of tape, a metre of string and one marshmallow, and eighteen minutes to build the tallest free-standing tower with the marshmallow on top. Everyone first predicts their tower's height. While the room builds, the big screen counts nothing; each time a team puts the marshmallow on top and lets go, a teammate logs on a phone whether it stood or fell. Then each team enters one measured height. Counts only, never names; each phone sees only its own team's log.

    Groups of 4

    Testing assumptions earlyIteration

    How it plays, and how to run it

Every activity here ships with Decka — sign up free and add any of them to your library from the built-in classroom catalog.

How it works

  1. 01

    Add it to your library

    Sign up free and pull the activity from Decka's built-in classroom catalog — one click copies it into your own library, ready to run from Decka or inside PowerPoint.

  2. 02

    Students join by QR

    Everyone scans from the projector and plays in their phone's browser. No app, no account, nothing to install.

  3. 03

    You run the room

    You move the activity phase by phase: collection closes, the boards resolve on the big screen, and the debrief happens while the results are still up.

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