Density Unit Day 1: The Cartesian Diver

I started with a "question of the day": What is density.  I tried not to confirm or deny any definitions or thoughts that the students have, and got a lot of "It is a property of matter", "The compactness of the particles" and "How dense something is".  I then introduced the Cartesian diver to them and told them to "play with it, and write down any questions you have (fig 1).  I said that there was one obvious question: "How does it work" but directed them to try and tease that apart and ask more specific questions.  They were told to write the Q's on their whiteboard.

I then wrote the Questions on an easel (Fig 2-4), and had them set up 3 columns in their lab notebook, one for Questions. one for Claim, One for evidence .  I had the students choose 5-6 questions, from the easel or their group list, and write hem in the "question" column(Fig. 5).

Fig 2 (period 2)

Fig. 3 (Period 1)

Fig. 4 (Period 3,
this period recorded their observations)

Fig 5. (Sample Lab notebook)

I was surprised at how many investigative questions I got . (like would it work with a rock? a pencil? different liquids? different size/shape bottles? different packets? etc.).  I guess I was expecting mote "how does it work" type questions.  I got some of the latter (Where does the water go [when you squeeze it]?  Does it have to do with pressure? and...  Is the air coming out of the ketchup?)


I discussed this with Marie and she suggested i have them write their observations first, so I did that with P3 (Fig 4).