Spaghetti and marshmallow tower

This activity is part of our Science Lab series. Check out the ANU Science Lab for more experiments! In this activity, you will construct a 3D pyramid structure known as the Martin Miller Tower using uncooked spaghetti and marshmallows to explore optimal 3D geometry, equilateral triangles, and structural stability. Watch the video above to see how it is done.

Spaghetti & marshmallow tower materials & ingredients

For this activity:

• Uncooked spaghetti strands
• Marshmallows (mini or standard size)
• A protractor

How to build a Martin Miller Tower: Step by step instructions

Step 1: Assemble the base geometry

1. Insert three equal-length strands of uncooked spaghetti into three marshmallows to form a flat, triangular base.
2. Adjust the base so it forms an equilateral triangle where each internal angle measures exactly 60°.

Step 2: Construct the 3D pyramid framework

1. Push three more spaghetti strands of equal length into each of the three base marshmallows, angling them inward toward the centre.
2. Connect the top ends of all three rising spaghetti strands together into a single apex marshmallow suspended above the base.
3. Check the internal angles between adjacent strands to confirm they maintain the 60° alignment throughout the 3D structure.

Step 3: Test and evaluate optimal stability

1. Observe how the 3D pyramid configuration resists twisting and swaying compared to 2D shapes.
2. Gently apply downward pressure at the top marshmallow apex to see how the weight distributes evenly across all three spaghetti legs down to the base.

Martin Miller Tower: The science explained

This geometry demonstration illustrates 3D structural optimisation, vector geometry, and material forces:

• Truss rigidity: Triangles are inherently rigid shapes because their side lengths fixedly determine their internal angles. Unlike squares or rectangles, a triangle cannot deform without altering the length of its sides.
• Compression and tension: The rigid spaghetti strands act as structural members under compression (pushing forces), while the flexible marshmallows act as nodes holding the joints together.
• Optimal 3D geometry: Extending 2D equilateral geometry into a 3D pyramid spreads load forces evenly across every structural member.
• Equilateral angle: An angle of 60° forms an equilateral triangle where all three sides experience identical force distribution under an applied load, minimizing stress concentrations and preventing structural failure.

Science fair projects & taking it further: Experimenting with variables

• Modular tower stacking: Stack multiple pyramid units on top of one another to create a taller Martin Miller Tower. How tall can you build before the bottom marshmallows begin to squish under the weight?
• Marshmallow firmness: Test fresh, soft marshmallows against marshmallows left out overnight to harden. How does joint stiffness affect the overall stability of the tower?
• Base geometry comparison: Compare a 3-legged triangular pyramid (tetrahedron) against a 4-legged square pyramid. Which base design supports the highest load-to-weight ratio?