Understanding Condensation

Monica HartmanMelvindale-Northern Allen

Park March 30, 2002

Question How does student understanding

of condensation develop during a science talk?

Teachers of science at all grade levels should be able to: Plan an inquiry-based science

program Take actions to guide and facilitate

learning Assess student learning Develop environments that enable

students to learn science (National Research Council, 1996)

Benefits of collaborative inquiry It creates multiple zones of proximal

development. (Vygotsky, 1978)

The cognitive load is spread among members enabling a higher level of achievement than would otherwise be possible.

(Wood, Bruner, & Ross, 1976)

Benefits of collaborative inquiry Conceptual change is more likely

to occur in environments that encourage questioning, evaluating and criticizing, and where dissatisfaction with the existing state of knowledge exists.

(Brown & Palincsar, 1989)

Science Talk Gallas argues that “the kinds of

talk and thinking that children engage in when studying science naturally parallel what both practicing scientists and historians of science report”

(Gallas, 1995, p. 13)

Benefits of Science Talks Creates a community of learners Provides an environment that

enables student inquiry and learning

Gives teachers opportunities for formative assessment

Context 5th grade science classroom Small suburban district outside

major city Mostly white, some Arabic and

African American students 35% receive free or reduced

lunch

Setting

As the district learning specialist, I modeled this lesson for a first year teacher.

The class was studying phase changes and getting ready to study weather.

Question for Students Where does the water on the

outside of container filled with ice come from?

Using a Pivotal Case I expected

students to say that the water came from inside the container when the ice melted. I colored the water blue before freezing.

Students’ Ideas The outside is kind of frozen a little

bit…so the outside of it kind of melts a little bit. (#1)

There’s ice inside and it’s cold and the air from the outside gets on it and it gets wet. (#2)

Ice melts to make water (#3)

Students’ Ideas It’s coming from the ice because the

heat is melting the ice. (#3) Ice is melting and turning to water. (#4) Maybe air pressure or pressure (#5) It gets out, out of the seal…when you

put pressure on top of it.. It will start like deforming, I think the word is, and then it just goes over to most of the sides when you press in the middle…(#6)

Students’ Ideas I agree with pressure, but it’s sort

of the heat that’s making it, because the heat hits the container, it makes it get warmer and the ice melts. (#3)

From the frost outside (#7) Ice melts and makes water. (#8) Several others agree (#7, #8, #9)

Turning points? The water doesn’t come from the inside

because it can’t come out. (#5) I tried something right now. I wiped the

water on the bottom and then it comes back every time. (#1)

Connecting to past experiences with water bottle – “moisture on the outside and air would make it more water”. (#2)

Students’ Ideas I think it’s water vapor. The water

comes out of it and gets on the outside. I don’t know. (#10)

It’s so hot around the container it starts to sweat with a whole bunch of water coming out of the inside. (#11)

My Pivotal Case If the ice is blue and you look

inside and see the water that had melted, do you see that the water is blue?

If the water we see outside the container is not blue, but we think it is coming from inside the container, why isn’t it blue?

Students’ Ideas It’s like what it does on winter days

on the window, where it comes from the inside and you can write on it or like on the bus…(#1)

The water on the outside isn’t blue because it’s sweat from the outside. (#12)

Do they have it? When you take it out of the freezer

and it gets kind of watery on the outside, but you don’t see it the same color because it’s like water that, water from..

Teacher: Water from where? Moisture in the air (#2) Several agree

Or Not? It’s coming from the ice (#1) It makes like sweat or water (#11) The water comes from the cooler.

The ice in the cooler that’s melting gets on the container. (#6, #13, #14)

Maybe there’s ice on the container you can’t see. (#10)

Developing ideas Air comes out. You see some air come out

of the freezer and that’s evaporation. (#15) I think water is coming from the air because

when you take it out of the freezer, you get hot air from the house and stuff and that’s where it is from. (#16)

Visible air that you can see goes on the container. The evaporated water gets on the sides..when the air hits the thing…I don’t know how to put it, the outside part gets wet somehow.

Constructing new understandings based on prior ideas I was looking at my water bottle. I’m

feeling it and looking around. Then I realize that when the heat hits the ice water, it makes something…it might make something like you get in the car all the time. Like when the heat and the cold mix, it hits the window and it makes…The heat from the car hits the car window from the inside and the cold hits the car from the outside.

Conclusion Students’ ideas about

condensation developed during the science talk.

The pivotal case was helpful, but some students offered pivotal cases of their own.

The science talk engaged the students and prepared them for the lessons that followed.

Implication for Instruction Science talks helps teachers find

out what students are thinking. Students formed new ideas from

listening to others. What if students’ newly formed

ideas are based on other students’ alternative conceptions?

Is it worth taking that chance?