Investigation of the kinetics of phosphorescence decay is a suitable learning task in studying the formal kinetics, and also properties of crystal phosphors. Kinetics of phosphorescence decay of crystal phosphors can be experimentally investigated at home as part of distance learning, using a conventional digital photo camera and a luminescent object such as a glow-in-the-dark toy. During the work, students get acquainted with the basic laws of phosphorescence decay kinetics and determine which law is observed in their object and what mechanism it corresponds to.