Credit where credit is due
We frequently discuss the importance of the mastery of hands-on lab skills in chemistry education. This is because a lack of such skills compromises the ability of students to explain phenomena based on experimental evidence and can lead to a failure to recognise the chemical context of problems encountered during instruction. Any observer of practical work will appreciate that students frequently employ incorrect technique, resulting in imprecise measurements that impact on calculations and subsequent explanations. A key factor in this is the lack of time for direct assessment of lab skills, with a reliance on post-lab written reports preventing the diagnosis and correction of poor technique. In this article, Marcy Towns and colleagues outline the benefits of digital badging in addressing these problems.
Digital badging provides a framework for the evidence-based assessment of performance and allows students to showcase skills they have learned. The authors draw the analogy with scouting, where badges denote the mastery of skills or the completion of tasks. This study evaluates the use of digital badging with the techniques of using a burette and making a solution in a volumetric flask. Instructors provided instructions to students to guide them in creating videos of themselves performing the techniques. Each submitted video was assessed before feedback was provided, with aspects such as the correct recording of burette readings being monitored. In cases where a video was rejected, students were able to submit an improved version for further assessment.
The study demonstrates the approach is scalable, with around 1700 approved videos being submitted across two courses. Approximately 250 of those had been resubmitted following constructive feedback on a failed submission. Each packet of 24 videos took 45–75 minutes to assess, although the authors note the process speeds up with experience. Analysis of survey data indicated that students reported statistically significant increases in knowledge, confidence and experience, while responses to related exam questions indicated that students had generally developed good knowledge of the principles underpinning the techniques.
Aside from the benefits of authentic assessment of hands-on skills, the authors point out that other educators and even employers could review students’ digital badges to evaluate evidence of their skills and knowledge to support recruitment processes, and they even claim that lab costs have been reduced thanks to a decrease in the incidence of breakages due to poor technique.
S Hensiek, et al., J. Chem. Ed., 2016, 93, 1847 (DOI 10.1021/acs.jchemed.6b00234)