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.