In this activity, learners become detectives and use chemistry to investigate fingerprints. Learners explore how oils and sweat on our hands contain charged molecules that attract to charged molecules on surfaces that we touch, leaving behind fingerprints. Using tiny particles from cornstarch or cocoa powder, learners can reveal these prints. A step-by-step instruction guide with pictures, discussion questions, and suggested activity extensions are included. Links to English & Spanish classroom style lessons are listed below.