Here is a full-fledged investigation of light waves, the electromagnetic spectrum, and element spectra. Physicists research a scientist that contributed to our understanding of the behavior of light. They take notes on your lecture, and then they experiment in the lab with the spectra of different elements. They use equations to calculate wavelenghts. Although the activity write up and handouts are not the most attractive, they are comprehensive and make a complete mini-unit on electromagnetic spectra.