A laboratory experiment that introduces fluorometry of chlorophyll "a" at the general chemistry level is described. The use of thin-layer chromatography to isolate chlorophyll "a" from spirulina and leaf matter enables quantification of small amounts of chlorophyll "a" via fluorometry. Student results were reasonably comparable to those found in the literature. This experiment uses relatively low volumes of organic solvents and an inexpensive fluorescence spectrometer (such as a Vernier SpectroVis Plus). The method could also be adapted for inquiry-based laboratories comparing chlorophyll a levels in plants, algae, and photosynthetic bacteria.