Making Rafts

Today me and my buddy had to make a raft that could hold 40 grams first we designed the raft in our project books and we come up with that the raft had 18 straws in the middle and a straw on the outside. then we had show the teacher our design then she gave a the the straws and tape next we our raft and then we had to put the raft on water and for a second I thought i was going to sink but it didn't.