shows sparks flying when a rotating grinder wheel is used to remove sharp points from screws while creating home-made mandolins. The photo, one of the top 100 in the 2024 AAPT H.S. Physics Photo Contest, is titled “Sparks of Knowledge,” by Muhammad Ahmad of Skaneateles High School (teacher: Daniel Kurzen, see https://aapt.org/Programs/PhotoContest/index.cfm). So much physics here!—the length of the spark paths, the directions, the colors, the brightness...what strikes you?