Forensic Science: DNA, Blood & Biological Evidence Blood Types & Blood Type Case

Forensic Science: DNA, Blood & Biological Evidence | Blood Types & Blood Type Elimination Case | Grades 9–12

Bring forensic science to life with this Blood Type Elimination Case, a no-prep investigation designed for high school students. Students explore the ABO blood group system, Rh factor, blood typing, class evidence, suspect elimination, and the connection between blood typing and DNA analysis while working through a realistic fictional forensic case.

Students first build their understanding of blood types and their use in forensic investigations. They then examine a case file involving blood recovered from a crime scene, compare the evidence with the blood types of six potential suspects, determine who can and cannot be eliminated, and justify their conclusions.
The investigation concludes by challenging students to consider the limitations of blood-type evidence and determine what additional evidence—such as DNA, fingerprints, surveillance footage, or trace evidence—would be needed to continue the investigation.

What's Included
- Teacher Directions with lesson flow, differentiation, teacher tips, and assessment ideas
- Student-friendly Blood Types & Forensic Science Overview
- Mini Research Questions
- Online research resources
- Group Activity directions
- Blood Type Evidence: Understand the Science activity
- Blood Type Elimination Case File with crime-scene evidence and six suspects
- Plan & Analyze the Evidence investigation worksheet
- Dig Deeper: What Does the Evidence Really Prove? critical-thinking activity
- Teacher Answer Key with suggested/model responses
- Full-color student materials
- Printer-friendly black-and-white student pages

Students Will
- Explain the ABO blood group system and Rh factor
- Interpret common blood-type designations
- Explore how blood typing has been used in forensic investigations
- Distinguish between class evidence and individual evidence
- Analyze blood evidence from a fictional crime scene
- Compare evidence with potential suspects
- Determine which suspects can be eliminated or not eliminated
- Support investigative decisions with evidence-based reasoning
- Explain why matching blood types do not establish individual identity
- Connect blood typing to DNA analysis and other forensic evidence
- Practice research, collaboration, analysis, and critical-thinking skills

Great For
- High School Forensic Science
- Forensic Biology / Forensic Serology
- Biology
- Anatomy & Physiology
- Crime Scene Investigation units
- STEM enrichment or elective courses
- Homeschool forensic science
- Sub plans, extension activities, or collaborative investigation days

Why Teachers Love This:
- Low prep and ready to use
- Designed for 1–2 class periods
- Engaging case-file investigation format
- Moves students from research → understanding → application → analysis
- Encourages evidence-based reasoning instead of simple recall
- Reinforces the difference between elimination and identification
- Includes a teacher answer key with model responses
- Works for individual, partner, or small-group instruction
- Easy to incorporate into an existing forensic science or biological evidence unit

⭐ Follow & Save!

Disclaimer
This is an independent educational resource created for classroom instruction. It is not affiliated with or endorsed by any law enforcement agency, forensic laboratory, government organization, or other organization referenced within the resource.
Forensic science may involve sensitive topics including crime, violence, blood, DNA, bodily fluids, injuries, death, and other biological evidence. Teachers should preview materials and determine their appropriateness for their students and school community. All forensic scenarios, DNA profiles, and investigative activities are provided for educational purposes only and are not intended as professional forensic, medical, or legal training.