On friday we did a review of the history of our world. We had to arrange index cards in chronological order. The group that I was in got everything in the right order, but had a minor question. One of our members thought that the astroid that hit earth was the permian extinction, but a quick note check clarified things. Our group worked really well together, and even if we agreed we shared our notes. We learned that humans were alive for such a such amount of the universes history. Most of our group thought humans where alive for 4-5 billion years, but Piper said we were wrong, but since she had no strong evidence, no one was convinced. But then we watched the history of the world in two hours, we realized she was right.