Raft Design

Our sixth graders continue to work on solving engineering problems based on fairy tales. This week, students were asked to design a raft to help the billy goats get across the river because the troll wouldn’t allow them cross the bridge.  The students could only use straws and rubber bands to make their rafts.  The rafts had to float completely for at least 10 seconds and hold at least 10 grams.  The students quickly discovered that water gets in the open ends of the straws, causing their rafts to sink.  Some students put rubber bands around the ends of the straws, while others bent their straws to prevent the water from getting in. This task isn’t as easy as it sounds! Take a look at the pictures of a few rafts floating in the sink.




Leave a Comment

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s