Inspire the CSI Miami generation with their own blood-soaked crime scene, says Karen Costello

Secondary: Ages 13-14

Hit TV shows such as CSI Miami, Waking the Dead and Silent Witness demonstrate that there is a huge interest in forensic science, so how can we capitalise on this when teaching science?

I attended a training workshop called “Fun with Forensics”, which led to a whole-year project for our school. With the help of a cross-curricular team from the art and science departments, we planned and then carried out a series of six lessons for 240 pupils.

Experiments were limited to four main forensic areas - blood, fingerprints, soil and footprint investigation and fibre analysis.

We started with a visit to a fictional crime scene, where a “former pupil” had gone “missing”. We added the classic body outline on the floor, planted fingerprints, a footprint, a bloodstained cloth and a blood stain on the floor, which was swabbed for further processing. The art department helped to make the crime scene look more realistic with liberal amounts of red paint, which enabled us to show and discuss a number of different blood-splatter patterns.

With a bit of creative lighting, the staged forensic evidence was ready to be examined by the pupils, photographed and removed back to their classrooms.

The examination focused on linking a suspect teacher to the crime scene - the classic whodunnit. We were careful to point out that the evidence must prove or disprove any links to the crime scene.

Pupils tested the cloth and swab samples to identify any blood samples. They went on to find out the blood group and used gel electrophoresis to see if the blood sample matched any of the suspect teachers’ DNA profiles.

The fingerprint investigation concentrated on why and how they are unique to individuals, and pupils managed to match the crime scene fingerprints to a suspect teacher.

Pupils used their knowledge of acids and alkalis to investigate the soil pH. The fibre analysis under a microscope was based around cases where it swung criminal convictions, such as the Atlanta child murders, the first case where the judge ruled it was admissible.

The project is a realistic introduction into how forensic science can solve crimes, which the pupils enjoyed.

Karen Costello teaches chemistry and science at Johnstone High, Renfrewshire.