To construct a bridge by using one piece of poster board and white glue. The bridge will support a cafeteria tray and three standard red bricks on its span.

The bridge must be:

• Height – 3 cm or more
• Length – 50 cm or more
• Span – 30 cm or more
• Poster Board – 70 cm X 55 cm

The bridge must use a minimum of five separate pieces of posterboard.

700 grams

45 cm X 35 cm X 2 cm deep

1850 grams

21 cm X 10 cm X 6 cm

Approximately 6300 grams / 14 pounds

45 cm X 35 cm X 2 cm deep

On the date assigned, students will bring a blue print type drawing of their bridge to class. The drawing should include details so that it shows individual pieces and their sizes. The drawing should help you build the bridge. It will be graded while you are building the bridge.

One class period will be used to build the bridge. No extra time can be used.

On the following day, students will present their bridges – explaining construction techniques, and reasons for these construction techniques. The bridge will then be tested!

The drawing and bridge must be completed on time using only the two materials supplied. The bridge may be decorated, however. Decorations can not be used as a means of support in any way.

You will test your bridge by placing the bricks on the cafeteria tray and the tray on the bridge so that it is centered on the span.

The bridge must be designed so that the tray and bricks can balance on it. You must let the tray balance for five seconds. You cannot be touching the tray during these five seconds.

After your bridge has been tested, you will be asked to write a paragraph on the project, noting lesson learned, mistakes made, and ways that you could have improved your results.