File Card Bridges

Today we did an inquiry about bridges. We used file cards (the ones people use to write their notes for giving speeches on) to make the bridges. We had to experiment using one and then two file cards. We also had to change the second file card to see if there was any way to make the bridge stronger. Some of us found that we could make our bridge much stronger by folding the second card accordian style and putting it underneath the first card for strength. See the picture. We also experimented with an arch. We saw lot of arches in one of our background lessons on structures. Finally we tried to change the length of our bridge. By the way-we measured the strength of our bridges by how many pennies it would hold up.