Did you know that there are more than half a million bridges in Canada? You rely them on everyday to cross obstacles like railroad tracks, roads, streams, and valleys. Do you know how they work? Why are some bridges curved and others are straight? Engineers have to think of many things - like the distance to be spanned and the types of materials available - before they decide on the size, shape, and overall look of a bridge.

As you tried out the different building acitivities your teacher set up for you over the last little while, you probably discovered a lot of things about bridges that you didn't know before. You're going to put your new knowledge and building abilities to work in this Bridge Challenge!

You got here just in time! The community park needs a new bridge to cross the river and you've been hired. Before the city will let you start building, the mayor wants to see a model of your bridge design. The mayor was heard to say "I want a one-of-kind bridge that will span the beautiful river and welcome visitors to our park." So...you want to be a bridge builder? Let's get started!

In order to cross the river, your model bridge must span a minimum of 50 cm and be at least 10 cm wide. Your model bridge needs to have have both strength and stability. This will be tested by seeing if can hold a load of at least 5 pounds.

You can provide anything you like to build your bridge model. Here are some ideas of things you might want to use:

You might be able to find some great stuff in your recycling box at home.

Step One:
You will be required to draw a design of your bridge before construction begins. You will need to hand this in as part of your project. Predict how much weight your bridge will be able to hold. Label the different strength and stability characteristics that you have used in your design.

Step Two:
You will now construct your bridge based on the design elements and materials that you have chosen to use.

Step Three:
Put your bridge to the test! Place it between two chairs and place a 5 pound weight on top. If the bridge can hold the weight, move on to adding more weight 1 lb at a time.

Step Four:
Record your findings.

Think of the following:

1. How much weight did your bridge hold?
2. What did you learn about constructing a bridge with strength and stability?
3. Would your bridge have reacted to the weight differently if the span was increased or decreased?
4. What would you change or do differently next time?

Step Five:
Present to the class the different characteristics of your bridge.

1. What did you choose to include or not include?
2. What kind of bridge design did you choose and why?
3. What would you have done differently in constructing your bridge?
4. What part of designing and constructing your bridge are you most proud of?
5. How did your findings relate to your predictions?
6. What have you learned from doing this task?

Step Six:
Your last part of the Science task is to create an advertisement selling your engineering abilities. Your poster advertisement should state why the city should choose you to construct this bridge in their park. Your advertisement should also contain the following:

1. Demonstrating features of strength and stability.
2. Demonstrating the features using scientific technology and language.
3. Be sure to include detail and some artistic component. It is an advertisement so it should have bold, bright colours and lettering.
4. Be sure to have created a name for your Engineering Firm/Company.

Be creative, have fun and remember what we have learned about creating and building strong and stable structures!

2. A letter may be used to tell your parents about this bridge building challenge. Two versions of this letter are available - Rich Text Format and PDF.

1. Here is the rubric that will be used to assess your final bridge design. Two versions are available - Rich Text Format and PDF.

2. You may find this Self Assessment useful. Two versions are available - Rich Text Format and PDF.

Congratulations!

You've successfully presented your model to the mayor and community park committee and are ready whenver they are to start the proejct. Now that you've completed this project, take time to consider the following questions:

What have you learned?

What did you like best about the task?

What might you do differently given the opportunity to do a similar task again?

If you are interested in learning more about this subject matter, you can find related hyperlinks at Student Links 2 on the LDCSB "Intranet" Website.

* Note: This link is not licensed for home use by students

This task was developed to help young students develop the skills of technological deisgn and building as well as to foster an appreciation for the many strengths and interests of their classmates.