Discussing the Need of Experimental Replication with 5th Grade Students Conducting a Mealworm Experiment

ABSTRACT

Scientific inquiry requires the replication of results in experimental studies. Recent studies draw a severe picture on the need of replication and the difficulties in replicating already published studies. As replicated confirmation of results is the basis of scientific and medical research, there may be a need to introduce the topic of replication to students. In an experiment, 5th grade students tested the effect of yeast addition on biomass increase in mealworm larvae. Each student took care of one larva on flour and one larva on flour + yeast (in total n = 30 larvae per treatment) in separate small boxes. After the experiment, students discussed the results of their two larvae. Subsequent pooling of the data in class showed a high degree of variation. When asked why replication in this experiment was important, students revealed a generally good epistemic understanding of the issue of replication and offered several explanations for why replication matters in experimentation.

Keywords:

• Replication
• experiment
• Tenebrio molitor
• scientific inquiry

Acknowledgements

I would like to thank Ruth Mahler-Hilwerling, who planned and conducted the experiment and the teaching sequence with great care and passion, and Philipp Westphal, who did parts of the evaluation of the experiment together with R.M.-H., both as part of their Master-thesis. The responsible classroom teacher, Melisa Cevera, supported us in many ways as well as 30 enthusiastic 5th graders (Albert-Schweitzer- /Geschwister-Scholl-Gymnasium, Marl, Germany). Klaus Reinhardt (TU Dresden) commented very helpfully on earlier versions of the manuscript as well as two anonymous reviewers.