It was a good opportunity for the students to familiarise themselves with a rigorous methodology and appreciate that practical work requires care, patience and does not always lead to an immediate result.
Preparation of growth medium in vials and a set of equipment for each student takes a fair amount of time, so this experiment is not carried out that often in schools.
These methods have reduced risks by not using Bunsen burners and flaming of equipment and are suitable for use with full classes. In this case the focus was on practical skills and particularly aseptic technique. Flaming was used as an additional means of reducing contamination.
The practical was based around the method described here