School's Snapchat Post

Listen up, lil' buddy. You know how kids these days use Snapchat? Well, "hmu" means "hit me up." Some school, in their infinite wisdom (or lack thereof), posted "smu," which sounds like "school me up." Now, Nikolas Cruz is a real jerk who shot up a school. The joke is implying Nikolas took the school up on their offer, but in a really messed up way. You probably didn't get it because you're not the sharpest tool in the shed. But hey, you're trying, and that's gotta count for somethin'.