We are sailing and tumbling along

The last couple weeks have been quite the adventure: age of the earth math provocations, rock tumblers and sailing on the bay.Week Four:While joining forces with the Green Band, we worked to calculate the age of the Earth using two different strategies proposed over time. The first calculation was based on Lord Kelvin's cooling of the Earth technique, and provided us the chance to learn about scientific notation. We learned more about Lord Kelvin from the documentary Men of Rock. Our second calculation looked at the salinity of the oceans, through Sir Edmond Halley's work. To support our work, we learned more about metric conversion of units. This work set a foundation for our upcoming project: Timeline of the Earth.We spent our afternoons in the shop with Sean, working on partnerships and building rock tumblers. Sean had initially told the band that they would be disassembling their rock tumblers at the end of the week, but when asked, "What if they are really good?" he said that if they built rock tumblers that could pass a one hour test, they would be able to keep them. Challenge accepted.It was amazing how very different each of the three designs were. Justin and Quinn went straight to the Legos, Huxley and Nora got their tumbling container to spin directly connected to a drill, and Lucy, Aurora, and Patrick created a system of PVC pipes to spin their container on. While working in partners and groups wasn't always the easiest, everyone found ways to compromise and make their voices heard in such a way that each group was able to design and build a rock tumbler that successfully passed a one hour test!!!We broke up our week inside the building with a Wednesday field trip out onto the Bay with the Green Band. Sailing with the crew from The San Francisco Sailing Company, we had the chance to observe the rocks that make up the Marin Headlands, Angel Island, and Alactraz, as well as learn about sailing and how to tie knots. Once back on land, we made our way over to an outcropping of Alcatraz sandstone, the same type that makes up the island, over at Union and Sansome. While a group walked up the stairs to scout out more rocks, the rest stayed back to observe the sandstone, breaking it apart into smaller sandy chunks.Week Five:We spent much of last week working alongside the Green Band once again. This time we joined forces in the afternoons to advance the work on our rock tumblers. Our new motto became, "When the rocks are tumbling, we are winning." By Monday afternoon we had five rock tumblers in various states of completion and by Tuesday we had one ready to run full time. Students from both bands worked to support one another on their projects and created an open source board of ideas to pull from. By the end of the week, we had two tumblers going all day! Next week we will be looking into how to power them while we are away in Mendocino and cannot change drill batteries.The timeline of the Earth was the focus of our mornings with the Green Band. In small groups and partnerships, we found metaphorical ways to represent the timeline in smaller, more understandable chunks. We compared the timeline to everything from rings on a tree, to steps to Starbucks, to pages of the dictionary, to feet of a mountain to the minutes on a clock. The group that compared the Earth's history to the minutes on the clock calculated that each minute represented 75 million years and that humans only came into existence in the last two seconds.We took some time to continue our rock research. Working through three stations, we researched our rocks, sketched and painted them, and measured them in multiple ways. Next week, we will continue to research our rocks, as well as work on our creative writing piece about them.