Crime Lab Chemistry

Grades 4—8

Written by Jacqueline Barber

Poirot never had it this good. In this unit's prime scenario, pegging the pen used to write a ransom note comes down to chromatography, a technique for separating mixtures into their (telling) component parts.

Challenged to determine which of several black pens was used to write the ransom note, student-detectives explore the concepts of solubility, pigments, and separation of mixtures as they use chromatography to ferret out the culprit. Ink is one of many substances for which the technique is used in science; the separation of blood and other constituents has become invaluable in real-world forensic science, and students' fascination with detective work makes a terrific springboard for further discussion.

Several mystery scenarios are possible, using nefarious characters drawn from any context you like; many teachers have cast themselves or the school principal as suspects!

Two excellent connecting GEMS units, Fingerprinting and Mystery Festival, also draw on detective work and mystery to explore the very essence of scientific inquiry.

Time: Two 35- to 45-minute sessions plus follow-up sessions.

See the Crime Lab Chemistry online orientation video.

Recommends   Crime Lab Chemistry
"This is an exceptionally well-written activity book featuring two experiments that help students learn the important science concepts of solubility, pigments, and separation of mixtures while solving a mystery. …I highly recommend Crime Lab Chemistry as a great way to introduce students to important science concepts. The activities are fun and intriguing, but they require students to use higher levels of thinking and scientific processes."

–National Science Teachers Association Recommends

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ISBN: Grade Level Format Price



2 Sessions,
36 pages


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