Notes for the Instructor Copy

In this lesson, students learn how shoe prints can reveal significant information in an investigation, even if the shoe print cannot be seen by the naked eye. This present but invisible shoe print is called a latent shoe print. To view it, forensic scientists may use an electrostatic wand to pull the dust from a shoe print off a piece of newsprint, for example, found at a crime scene. The dust is transferred and adheres to a thin plastic film. If the film is lit at the right angle, the shoe print will appear in detail.

In the first activity, students make their own latent shoe prints that appear “magically” after they apply printing powder. They write their observations in a data table and compare this with their partners’ shoe prints. In a second activity, students analyze a print of the suspect’s shoe tread pattern from the crime scene and match it to the patterns of shoe prints belonging to the four suspects.

The most common way forensic scientists look at a shoe print impression is by examining it under standard laboratory lighting or ultraviolet light. Another simple technique is to make a cast of a shoe impression with dental molding material. This technique generally enhances the quality of the shoe print impression because a three-dimensional cast gives the examiner more information from which to work in making comparisons.

The activities in this lesson address Next Generation Science Standards practices of Asking Questions and Defining Problems, Planning and Carrying Out Investigations, and Engaging in Argument from Evidence. In addition, they address Common Core State Standards CCSS.ELA-Literacy. CCRA. SL.1, CCSS.ELA-Literacy.CCRA.SL.2, and CCSS. Math.Content.3.MD.B.4.See the Standards Matrix included in the appendix for more detailed information.