In this lesson plan, students will learn about Dr. Elmer Imes, the second African-American to receive a Ph.D. in physics in 1918 and a physics professor at Fisk University. Students will learn about Imes’ experimental work on spectroscopy and how it was a turning point in modern applied physics. Afterward, students will learn about the principles of spectroscopy. This lesson explores Imes’ personal history and scientific work in spectroscopy, and provides a hands-on activity demonstrating refraction and spectra. Note: this lesson works very well alongside the AIP Teaching Guide “Physicist Activist: Dr. Elmer Imes and the Civil Rights Case of Juliette Derricotte,” which explores a historical tragedy that Elmer Imes became involved in.