Soap Film Models

Pintozzi, Joan                                    Curie Metro. H.S.
7200 Grand                                        838-5040
Downers Grove, Il. 60516
964-4216

Objectives:

1. Encourage students to conjecture
2. Introduce concept of minimum path and minimum surface area
3. Practice measurement of line segments and angles

Apparatus Needed:

1. Four inch square plastic models
2. Polygon models
3. Soap bubble liquid
4. Overhead projector
5. Clear shallow container to hold models on overhead
6. Rulers
7. Protractors
8. Worksheets with configurations of points like the plastic models

Recommended Strategy:

1. Have students draw line segments on the worksheets, to indicate 
   their estimate of the shortest path joining the points in the configuration 
2. Dip models into soap liquid
3. Show results on overhead projector
4. Encourage students to estimate and to discover patterns
5. Measure segments and angles drawn on worksheets and compare estimates to 
   experimental results
6. Summarize