Lesson 4: Natural or Not: Fiber Identification Copy

Lesson 4: Natural or Not!

Weave together the threads of a crime in an activity that allows learners to practice a proven technique in forensic fiber analysis. Then put on your deerstalker and set your Sherlockian sights on classifying the evidence. It’s elementary, dear Watson!

Have students practice using the tweezers and hand lenses before you begin the activity.

Lesson Objectives

  • Test and record observations of 4 types of fiber samples
  • Observe a heat-test demonstration, called pyrolysis, on fiber samples
  • Analyze the properties of fiber samples and record the findings in tables
  • Match the fiber found at the crime scene with a fiber type

Next, simply click the links below for further instructions and steps on how to get started!


  • black fabric: nylon, cotton, wool and acetate
  • aluminum tray
  • matches (must obtain your own)
  • container (for water)
  • votive candles
  • tweezers
  • metal tongs
  • wide clear tape
  • black marker
  • 5 sheets of light-colored construction paper
  • scissors
  • Student Book pages (on Resource CD)

Students (Groups of Three)

  • 3 pencils
  • 1 pair of tweezers
  • 1 hand lens
  • 1 pair of scissors