Grow amazing crystals that glow in the dark! With the Glow-in-the-Dark Crystal Growing Kit, kids will enjoy a classic hands-on experiment with a twist: these crystals glow in the dark! Children will love growing their very own glowing crystal. Put on your lab coat, follow the instructions, and watch your crystal grow! When your experiment is complete, compare your own glowing crystal to a real fluorite specimen. 6+ years.