- Before the session, pack one kit per team in a paper bag: 20 sticks of dry spaghetti, about 90 cm (1 yard) of masking tape, about 90 cm (1 yard) of string, one standard-size marshmallow and a pair of scissors. Prepare a visible timer and a measuring tape.
- Form teams of three to six people; four works well. Mix departments if you can.
- Explain the goal: build the tallest structure that stands on its own, with the whole marshmallow on top.
- Explain the rules. Teams may use only what is in the kit, not the bag itself. They may cut or break the spaghetti, tape and string. The structure cannot hang from a chair, light or ceiling.
- Start the 18-minute timer. Call out the time left at 10, 5 and 1 minute.
- When time is up, everyone lets go. A tower that someone is still holding does not count.
- Measure each standing tower from the tabletop to the top of the marshmallow. Announce the tallest, and recognise every team whose tower stayed up.
- Run the debrief for about 15 minutes, using the questions below.
Marshmallow Challenge: Team Problem-Solving Activity
Teams have 18 minutes to build the tallest free-standing spaghetti tower with a marshmallow on top. A lively lesson in testing ideas early.
- Group size
- 8–40 people
- Time
- 45 minutes
- Setting
- Indoor
- Materials
- Dry spaghetti, masking tape, string, marshmallows, scissors, paper bags
- Good for
- Onboarding, Company retreat
Objective
Show teams how planning, testing and shared roles affect results under time pressure. The task looks simple, but towers often bend or fall once the marshmallow goes on. Teams that test early often do better, which makes for a strong debrief on how you run real projects.
Steps
Example session
Here is how it might play out at a company retreat with 24 staff in six teams of four. Most teams spend the first ten minutes planning tall designs and add the marshmallow only near the end. In the final minute, three towers bend and fall under its weight. One team puts the marshmallow on a small tower within five minutes, then builds upwards, and ends with the tallest standing tower. In the debrief, the group can link this to a recent project where a key assumption was tested too late.
Debrief questions
- When did your team first put the marshmallow on top, and what happened?
- How did your team make decisions? Who led, and how was that decided?
- What would you do differently with another 18 minutes?
- In our real work, what is our "marshmallow": the risky assumption we test too late?
- How can we test ideas earlier on our next project?
Tips
- Use halal-certified marshmallows. Some marshmallows contain gelatin from pork, so check the pack for a halal logo such as JAKIM's.
- Stay neutral during the build. Answer questions about the rules only, so teams learn from their own choices.
- Dry spaghetti can snap into sharp pieces, so ask people to handle it with care. Do not let anyone eat the materials.
- Take a photo of each tower before you measure. The photos help during the debrief.
- Share the research after the debrief, not before. Tom Wujec, who popularised the challenge, reports that young children often beat business school graduates because they test early and often.
- Praise good teamwork, not just height. This keeps less confident staff engaged.
Variations
- Second round: after the debrief, give each team a new kit and 10 minutes. Compare heights to show the value of learning from the first try.
- Large groups: run up to 10 teams at once, with one helper for every five teams to time and measure.
- Leadership focus: secretly ask one person per team to act as leader, then discuss how leadership affected the result.
- Prize round: offer a small prize for the tallest tower, then discuss in the debrief how the pressure changed each team's behaviour.