Activity Introduction
Quick summary: In this lesson, students will learn about bloodstains are analysed.
Learning intentions:
- Students will understand what a bloodstain is
- Students will understand how to analyse bloodstains.
21st century skills:
Australian Curriculum Mapping
Content descriptions:
Year 10 Science
- Scientific understanding, including models and theories, is contestable and is refined over time through a process of review by the scientific community (ACSHE191)
- People use scientific knowledge to evaluate whether they accept claims, explanations or predictions, and advances in science can affect people’s lives, including generating new career opportunities (ACSHE194)
Syllabus outcomes: SC5-12ES, SC5-13ES
General capabilities: Literacy, Critical and Creative Thinking, Ethical Understanding
Relevant parts of Year 10 achievement standards: Students evaluate the validity and reliability of claims made in secondary sources with reference to currently held scientific views, the quality of the methodology and the evidence cited. They construct evidence-based arguments and select appropriate representations and text types to communicate science ideas for specific purposes.
Topic: STEM
This lesson is part of the wider unit of work: Real-life CSI – Secondary
Time required: 65 mins.
Level of teacher scaffolding: High – there is likely to be quite a lot of explanation needed, as well as students requiring assistance during the practical part of the lesson.
Resources required:
These materials are per group. Suggested group size of two to three students.
Experiment 1: Release height
- Graph paper
- Measures: 30cm and 100cm rule
- Newspaper
- Pencil
- Pipette or bottle with eye-dropper (something that will accurately deliver one drop of fluid with a consistent volume)
- Plain paper (to make label sheets)
- Stand and clamp – something to attach the pipette or bottle holding the synthetic blood.
- Synthetic blood (see https://www.scribd.com/document/156835304/FSB06 for recipes).
Experiment 2: Impact surface
- Graph paper
- Pencil
- Materials with different surfaces. E.g., cardboard, plastic bag, ceramic tile, carpet square, paper towel, wood, newspaper, metal, clothing (socks, jeans, T-shirt, etc.)
- Measures: 30cm and 100cm ruler
- Pipette or bottle with eyedropper
- Stand and clamp
- Synthetic blood (see https://www.scribd.com/document/156835304/FSB06 for recipes).
Experiment 3: Direction of travel
- 30cm rulers
- Pencils
- Plain paper to make copies of:
- Sheet A: A prepared sheet of bloodstains with information about how the bloodstains were created.
- Dip a toothbrush in the simulated blood and fling droplets from the toothbrush as your arm moves across the paper in a definite direction, e.g. R→ L.
- Label the paper with a general description of the action. E.g. R→ L direction, with the angle changing from shoulder to paper level.
- Sheet B: A prepared sheet of bloodstains with NO information about how the bloodstains were created.
- Dip the toothbrush in the simulated blood.
- Place your elbow on the table, and, using a protractor, position your arm at a predetermined angle, eg 45 degrees.
- Keeping the arm at the measured angle, fling droplets off the toothbrush as your arm moves across the paper, e.g. R→ L.
- Do not provide a description of your actions, but make sure you record them for later.
- Sheet A: A prepared sheet of bloodstains with information about how the bloodstains were created.
- Synthetic blood (see https://www.scribd.com/document/156835304/FSB06 for recipes).
- Student Worksheets (one per group)
- Toothbrush
Keywords: Forensic Science, Crime Scene Investigation, Evidence, Trace Evidence, Fingerprints, Impressions, Blood splatter, Kastle-Meyer Test, Hair, Science, STEM, STEAM, photography.
Cool Australia’s curriculum team continually reviews and refines our resources to be in line with changes to the Australian Curriculum.
Teacher Preparation
