US researchers investigated how much students learn through classroom discussions on scientific topics
Researchers in the US investigated how much students learn through classroom discussions on scientific topics.1 Dionne Cross and Daniel Hickey of Indiana University, Gita Taasoobshirazi of the University of Nevada, and Sean Hendricks of the University of Georgia studied 28 16-17-year olds at a high school in Georgia. Using a computer simulation program, the students had to manipulate variables, eg balancing food intake against physical activity, to keep alive six astronauts on the surface of the moon.
The work was divided into four sections and at the end of each section the students answered questions, giving explanations for their answers, and then took part in structured discussions with other students based on what they had written. The groups had to come up with the most sensible solutions for keeping the astronauts alive.
Teachers then provided additional explanations and the groups checked how this new information supported their explanations. The students were also shown an animated video in which the characters were discussing similar issues. The researchers studied one of the groups in depth by looking at videos of all the discussions and analysing the conversations that took place.
Observations of the groups showed that the dialogue was broadly similar across the whole class. Using pre- and post-test scores to measure the learning that had taken place, the researchers identified that a key factor affecting students' learning was the quality of their arguments.
Students who were able to provide evidence to contradict other evidence, and those who could recognise the limitations of a claim, scored well in the tests. Students also made good progress if they had a sound understanding of the scientific topics related to this new work. Using this knowledge, they were able to build their arguments with confidence whereas others tended to follow, finding it difficult to substantiate their arguments and needing support from their peers.
D. Cross et al, Int. J. Sci. Educ., 2008, 30 (6), 837.