RAYS (Roman Association of Young Scientists) is a group of young Master and Ph.D. students in Physics of the University of Rome La Sapienza, with a huge passion for the wonders of light and for teaching. RAYS are born in 2015 within the university, with the support of the Quantum Optics and Quantum Information group and thanks to two international organizations working in Optics and Photonics, OSA (Optical Society of America) and SPIE (The international society for optics and photonics). In just few months, RAYS began standing out by organizing seminars and conferences in the university, involving a larger and larger number of students and finally appearing in high schools where they had free rein with what they know better: describing to students the properties of light, with practical demonstrations as simple, as striking and as fun as you cannot even imagine!