Picture of The Clean Getaway Lab
This is a lesson I use to introduce my physics students to the process of scientific investigation including writing a problem statement, generating a hypothesis, collecting and organizing data, analyzing data, writing a conclusion that is supported by data, and communicating results in a lab report. It also serves as a motivational activity to get students excited about investigating the world around them.

I present the class with the challenge of determining what happened at the scene of the "Clean Getaway." I provide them with a series of digital photos taken of parts of the floor at the crime scene. Each photo includes a protractor for scale.
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Step 1: Required Materials

Picture of Required Materials
blood splatter equip.jpg
Materials for making fake blood:

shampoo (this is why its called the clean getaway!)
a generous amount of red food coloring
a few drops of blue food coloring

The amount of coloring you need depends on the original color of the shampoo. Once you think you have a good color, smear a little on white paper to see the color.

Other materials:

disposable gloves for students
lab aprons for students
large knife smeared with fake blood and put inside evidence bag (I used a plastic baggie with a zipper closure.)
supply of fake blood for students
prepared crime science blood spatters
meter sticks
ring stands
small boards
masking tape
graph paper
digital camera
access to a computer
photo analysis software

Step 2: Preparing the Crime Scene Splatters

Picture of Preparing the Crime Scene Splatters
exhibit A photo.JPG
To prepare the blood splatter for the students to analyze, smear the fake blood on the knife and use several different motions to create splatter on a piece of graph paper.

Once the fake blood has dried a little, place a protractor on the paper and photograph it from directly above the paper.

I created six different crime scene photographs so that each of my lab groups had a separate photograph to analyze during the activity.
kengberg7 months ago

Nice, could you say a little more about the experiments the students do?

They have a pipette, some "blood" and paper, and then the just try - and messure?

I'd love to see an example report..

ZeWeX1 year ago
Good work ! It is an amazing tool that helps students build their own investigation plan strategies :)
M.C. Langer3 years ago
Simple but powerful. I love it! You have my vote. AWESOME!!!!
CitizenScientist (author) 3 years ago
Thanks! I used it for the first time this fall to start the school year and the kids did a great job. It's fun to watch them develop and follow through their plans.
wilgubeast3 years ago
This is super awesome. I really like the rubrics, too. This is a WONDERFUL resource for teachers. Thanks for sharing!