We started the school year in sweltering heat (the school has air conditioning but they are replacing all of the cooling/heating systems - yes, they waited until September to do this).
I wrote about today's plan here, including the handout. Here is what it looked like as students added marbles to the water and measured the height:
Overall my class worked really well. I circulated and learned all their names and helped out when they were stuck. Most did a good job of collecting and recording data and creating a scatter plot. Some had reversed the independent and dependent variables which prompted some good discussions. I am much more aware of my questioning and am trying not to lead them with my questions. They were very good at realizing that neither the table nor the graph would allow them to determine the number of marbles to reach the top of the glass. There were lots of conversations around the y-intercept and slope which I tried to steer back to the context of number of marbles and height of the water so that those numbers had meaning. One group said they calculated the slope to be 5.4. When I asked "5.4 what?", and they replied cm per marble, they immediately realized that their answer didn't make sense. We didn't get a chance to test their models so will start with that tomorrow.