Straw Bridges at Reavis

This week in Sisters4Science, the girls at Reavis explored engineering! First, we talked about how we would modify or change something about the world or about ourselves to make it better. Trushana wanted to make herself faster and stronger, and Kemonte had the idea to encourage people to clean up after themselves to make the world better. All of the girls had some great ideas for how to fix world problems!

Now that we talked about how to fix problems in general, we turned to a specific example. Engineering, after all, is about planning and modifying things to make them work as well as possible.
The Challenge: to build a bridge that could cross a 25 cm gap between two tables
The Materials: 20 plastic straws and tape
The Teams: Trushana, Kemonte, and Aaliyah vs. Tiana and Alita
The Competition: the winning bridge would be the one that could hold the largest number of paperclips without breaking
Each time took some time to plan out their bridge, including measuring how long it had to be to cross the gap, and thinking about how to make it stronger. Then, we started building. There were straws being taped side-to-side and straws being taped end-to-end, and great discussions about how wide it would have to be to hold the cup with the paperclips and how long it would have to be to balance on either side of the gap.
Finally, we tested it!
Team #1 (Trushana, Kemonte, and Aaliyah) were able to place 42 paperclips into the styrofoam cup on their bridge before it tilted to the side and fell.
Team #2 (Tiana and Alita) placed 75 paperclips on their bridge before it collapsed!
After the challenge (and clean-up!), we talked about how to improve bridge structures. We learned that a truss (a series of triangles) was the most stable way to build a bridge because it would distribute the weight evenly.
Overall, both of the bridges were very impressive. Great job, Sisters!

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