Connecting theory to practice in the teaching laboratory

Group of teenage students in a science class with teacher

Source: © Shutterstock

There has been a move towards student-centred, inquiry-based approaches to chemistry practical work in recent years. However, for some academics the lack of time and confidence to innovate has slowed progress. In this article, Andrea Van Duzor at Chicago State University, US, describes a road test of one straightforward solution. She tests the use of a laboratory notebook and a writing-to-learn method which elicits self-explanations of procedures and outcomes from students.

The author has previously described the Decision/Explanation/Observation/Inference (DEOI) method, to introduce a student-centered focus to otherwise traditional experiments. Students make notes on procedural steps in the decision column, supporting the notion that they are actively conducting the experiment. They then write reasons for experimental design, along with discussion of what is occurring at a molecular level, in the explanation column. Under observation, students record measurements, spectral data and other pertinent observations. Finally, students write and justify their interpretation of observations in the inference column. This approach is a more authentic reflection of the way chemists think in the laboratory than is experienced when writing a traditional lab report.

The DEOI approach was devised to overcome the issue that students who could obtain products in organic chemistry practicals with high yield and purity were often found to be unable to state what exactly was in their flask during a reaction. This paper discussed work that probed the impact of DEOI on students through observation and interview, and indicated that the approach was perceived to be beneficial. Students commented that they had to think explicitly about what they were doing, thus aiding understanding, and it was recognised that writing explanations was a key factor in this outcome. It was also suggested that engagement with DEOI supported students in developing the ability to come up with subsequent questions regarding the rationale for features of experiments themselves.

Interestingly, it was noted that DEOI might be less effective when used with problem-based laboratories. Nonetheless, there is strong evidence that DEOI supports students in achieving enhanced outcomes during laboratory work, and the success of the approach has facilitated buy-in from colleagues at the host institution supporting the implementation of future innovations.