Building Bridges

Author
Lindsay @ Strawbees

Build a bridge to help Mio cross over a river safely!

Engineering
Science

Duration

2 x 45-minute Periods

Class Size

30 Students

Group Size

Individual

Overview

Bridges are very important for connecting places and allowing us to travel easily. Students will listen to the story of Mio arriving at a problem of trying to cross a bridge to make it to Mia's house in time for her birthday! Use Strawbees and straws to make a bridge between two surfaces over a river. Students at the end will collaborate and make the longest running bridge they can!

Materials

Straws
300 x Straws
2-Legged Strawbee
300
1-Legged Strawbees
300
3-Legged Strawbee
300
Scissors
30
Tissue Paper
20
Cardstock Paper
40
Pencils
15

Modifications

Lesson Split Time

Depending on needs, this lesson can be split and taught in two 45-minute periods. With a 15 minute break seperating two sessions for a break or clean-up. An additional 15 minute session at the end is for clean-up.

Learning Objectives

Learn the engineering design process: begin to recognize a problem, build a prototype to test, start iteration, and share the results with classmates.

Building the spatial reasoning capacity to visualize objects in three dimensions and beginning to draw conclusions about those objects from limited information.

Gain the ability to describe what was built using basic engineering vocabulary and demonstrate knowledge by identifying parts of their creation that work.

Fine-tune motor skills with tools and assembling materials together.

Understanding a story with a beginning, middle, and end with a problem and/or conflict with a solution.

Preparation

1

To add extra flair to story time, cut out shapes relevant to the scene. Create props from construction paper or felt to add to the scene.

2

Have additional small caddies or bowls around the room on desks or the floor to collect cut or broken straws pieces to save for future projects and help with cleanup.

3

Place containers of materials to the side of the room until students are ready to build.

4

For adding the deck/flooring of the bridge, you can cut sheets of paper into thick strips or long sheets for students to add on top for Mio to safely cross over in the bridge design.

Lesson Steps

1. Welcome

Who plans, designs, and builds bridges? Some of our community helpers do! Civil Engineers plan and design bridges for our construction crews to build. These important community helpers get us where we need to go, especially if we have to cross large bodies of water like rivers. There’s a lot of work that goes into building bridges, and it takes special skills to create a safe bridge for your community.

2. Story Time: The River

Start with the fun story of Mio going on a hike. You can choose to add sound effects, make body gestures, or making noise with your hands or feet to add an extra flair of fun for your storytelling.

"Mio was walking on a beautiful, sunny day on his way to a friend's house. Mio knew that the house was near the river down the road and it took him exactly 21 minutes of walking to get there. Today in particular, was his friend Mia's birthday! Naturally Mio did not want to be late, so he packed up treats in a basket and a beautiful scarf for her to wear. He left his house and begin his walk. 11 minutes into his walk, Mio saw the bridge he used to normally cross over, was gone!"

"Mio gasped! He was going to be late and to be late for a birthday party was no good indeed. He had to figure out cross .. but how?"

"Then Mio had a lightbulb! Reaching into his pocket he realized he was prepared. Fortunately, Mio always carries Strawbees and straws, a favorite toy that both be and Mia enjoy. What can Mio build to cross the river?"

3. How Do Bridges Work?

Introduce to your students that Mio, the engineer must take into consideration many things when planning a bridge or even fixing an old bridge. Ask your students the following questions:

How long must the bridge be? What is the water like? What is the land around the water like? Rocky, muddy, sandy? What materials should be used to build the bridge? What style should the bridge be? How can we cross over safely without going into the water?

4. Make a Bridge!

Pass out straws and Strawbees to your students to start to build a bridge between the two surfaces. Students can assemble simple bridges by connecting straws with 2-Legged Strawbees and make long rows of them. They can also slide straws through the heads of the 2-Legged Strawbees to build a basic form that will give the bridge strength.

Remind your students that the challenge is to build a bridge between two surfaces, such as stools, tables, or even cardboard boxes.

5. Crossing the Bridges

Have your students place their bridges on top of both surfaces to make sure Mio can cross over! Ask your students, "Do we see holes on the bridge?" If they say yes, have them point where they are and try to patch them up with paper or even laying down more straws. This will allow Mio to cross safely over.

Place a small sheet of paper on top to build a floor for Mio to walk across. You can test the bridge by carefully pressing down on the sheets of paper. Encourage your students to patch all the holes so Mio won't fall into the river!

For extra collaborative fun, you can challenge your students to combine their bridges to make an extra long bridge between multiple surfaces!

6. Finishing the Story and Reflection

Thank your students for helping Mio to cross the bridge as helpers of the community! Mio thanks everyone and was able to safely make it across the bridge to Mia's house! By building these bridges share that your students worked together as designers and engineers to build a safe bridges for Mio and anyone else afterward.

Bridges are very important for connecting places and allowing us to travel between places. Ask your students to raise their hands if they have seen a bridge near their house? If so, ask if they cross it and if they do, point out the parts of the bridge that makes it work! After learning this lesson, ask your students if they think they can build that bridge out of Strawbees.

Vocabulary

Bridge
A built structure creating a pathway over an obstacle.
Bend
When an object is pushed down and begins to flex.
Limit
A set restriction on what can be done.
Build
Combination of materials to construct a whole object.
Floor
The surface of a building.
Strength
The physical capability of endurance and resistance of force.

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