Reiterate that teams only have 18 minutes and then start the countdown timer and music to flag off the challenge.
- Observe and walk the room: Notice how teams get along and peep how they build and innovate their structure.
- Draw the teams’ attention to time: Audibly countdown the time at specific intervals. You can call when it’s halfway through (9 minutes), 5 minutes, 3 minutes, a minute, and a final 15 seconds countdown.
- Comment on the progress of each team: Raise the bar by encouraging and subtly praising teams that make notable progress. Build healthy competition by inviting teams to take a peek at each other’s work.
- Emphasize that holders will be disqualified: Some teams will be tempted to hold or support their structure at the end of the challenge. This is often done in a desperate bid to keep the last marshmallow they placed on their structure before time ran out. The building that wins needs to be free-standing and stable.