Lesson 3: Seams and Seals: Engineering an Airtight Envelope

1. How does the weight of the glue affect our "Lift-to-Weight" ratio?

2. Where are the most common points for air leaks in a tissue paper structure?

Envelope, Lap Joint, Seam, Porosity, Structural Integrity.

ENG.02.05: Identify and build a prototype.

ENG.04.01: Identify properties of materials (tissue paper porousness vs. glue seals).

This is the core construction phase. Students learn to apply a 1/4 inch bead of glue along the edge of the gore to create a "seal." They must troubleshoot "puckering" or "leaks" as they join the final gore.

Purpose: To practice the persistence required for high-stakes assembly.

DOK Level: Level 3 (Strategic Thinking).

Pair students into "Glue Crews"—one student applies the adhesive while the other aligns the paper to ensure even seams.

The "Flashlight Leak Test": A flashlight is placed inside the semi-inflated balloon to look for pinholes or gaps in the seams.

Glue sticks or liquid glue with precision tips, clothespegs (to hold seams), light tables or flashlights.