What are we doing to help kids achieve and learn?
Each year we do an activity that involves Archimedes principle. You might wonder...why do this in chemistry? Leading up to the activity, students do a series of labs and activities that involve measuring, accuracy, precision, significant numbers and density. The culminating guided inquiry activity takes place by which students take an object, find the volume in multiple fluids and find the mass in multiple fluids. An examination of class data starts to show that the volume of a solid does not change in fluids but the mass in air and the mass in different fluids are different. They also use the density of the fluid and the volume of the fluid displaced by the submerged mass to find the mass of the fluid displaced. The hope is to guide student's thinking to help them understand that the apparent loss of mass, or the buoyant force of the fluid against the mass is the same as the mass of the fluid displaced. In theory, this should be a great lab. The reality is that the instruments we have are less then ideal, it is tough to guide students with bad data and there are many connections that need to be made.
So...to bolster things a bit, I gave them a challenge. I found something called an "Archimedes Balance" from Educational Innovations. Students were provided with a mass, a graduated cylinder and a plastic "boat" that would fit inside the graduated cylinder. They were told to find the density of the mass....without the use of a balance. They were also told that it was extra credit and they could do it any way they wanted...as long as they came up with an answer, provided data and clearly explained why they did what they did. Students went crazy...they came in before school, after school and stopped me in the hallway. The majority of the time I tried to play stupid (I know...I'm opening a door wide open...). Most struggled, talked, experimented and struggled some more but came up with reasonably good ideas...in other words...they were really acting like real scientists. Maybe the word got out about how hard the test was and the extra credit was appealing. Maybe most students like being real scientists instead of answering questions on paper. Anyway..somehow, I would love to bottle that. What do you do that gets students really active and going. I would love to hear from you.