Cook-Wissahickon Elementary
Fall 1996
Teachers: John Sole, Lynn Hull, Grade 4
Guest Contractor: Paul Ricker
Web Site/ WHYY Project
The Henry Avenue Bridge is walking distance from the school. The students
studied the history of the bridge, sketched the bridge from different angles, took
photos, and made a preliminary model. They used a trundle wheel to measure the span of the
bridge, and a plumb line and plumb bob to determine the height of the bridge over
Wissahickon Creek. They used Math Explorer Calculator to learn about ratio, proportion and
scale, and to work out a scale so that their final model would fit on a table top. Their
model has a steel skeleton and stone facing just like the real Henry Avenue Bridge. They made
templates for the bridge from cardboard, created
the arches from screen and steel, using wire cutters and electric drills
and screwdrivers. They made the "sandwiches", the two sides of the
bridge, and connected them with screws and bolts. They went to Daisy
Field Quarry to collect Wissahickon Schist to use to clad the bridge.
They used ratio and proportion again to mix the mortar for the stone.
They worked with partners to connect the arch pieces to make the bridge.
Later they cemented it. They went to Channel 12 to tape a video on their
project. Some of the students got to "walk" across the bridge on the
video, while others explained how the bridge was constructed.
