A kit and method for growing crystals for educational purposes. The kit consists of a small plastic petri dish, and a paper substrate with short and long slits precut therein that act as seed, respectively, for the formation of single and multiply crystals. The disk of paper has a tab that serves as a handle for placing and removing the disk from the petri dish and as a place to write on the disk. The kit is used by pouring a saturated aqueous salt solution in the bottom of the petri dish and then floating the substrate on the top of the solution. The dish is then allowed to sit uncovered for several days and crystals grow on the bottom surface of the substrate as the liquid evaporates.