Why should students engage in argumentation?

Consider this scenario:

Two students pour sugar grains into a glass of hot water. Once the sugar is poured into the water, it is stirred. After stirring, the sugar can no longer be seen. Why can we no longer see the sugar?

Which response would you like from your students?

a) The sugar dissolves.
The sugar has just mixed into the water. Sugar tastes sweet and the sugar and water mixture tastes sweet, so there is evidence that the sugar is still there. If the sugar was no longer there, the mixture wouldn’t taste sweet, so that idea doesn’t make sense.

Reason #1: When students engage in argumentation, their understanding of scientific concepts and the nature of science improves (Professor Jonathan Osborne's article in Science)

Concept Maps on the Topics of Food and Healthy Eating
Pre-intervention mean score Post-intervention mean score
Control group 1.08 3.97
Experimental group 1.52 6.02

Mercer, Neil, Dawes, L., Wegerif, R., & Sams, Claire. (2004). Reasoning as a scientist: ways of helping children to use language to learn science. British Education Research Journal, 30(3), 359-377.

9 and 10 year-old students participated in the study. The experimental group engaged in science lessons that explicitly taught skills such as critical questioning, sharing information, or negotiating a decision. The intervention had an effect size of 0.72, which is large.

Reason #2: Argumentation is central to science.

The history of science in the European tradition is the history of vision and argument. – Alistair Crombie, Historian of Science

Scientists routinely debate theories, their data, and the implications. They construct and critique arguments

(Osborne, 2010)

Watson and Crick critiqued other arguments.

Reason #3: Argument from evidence is a core practice in the Next Generation Science Standards and it will be assessed.

Figure 3-1 from A Framework for K-12 Science Education

Evaluating: Argumentation is the process of using evidence and reasoning to determine which of competing ideas about the natural world is best.

In science, argument is a core practice used to evaluate theories and models against the data and evidence gathered from investigations.

Professor Jonathan Osborne explains the rationale for engaging students in argumentation in science. He also sketches out ideas about argumentation that informed our assessment items.