This started, like, 3 years ago? Something like that. At one point I found myself with access to colored paper and a birthday boy/girl in class. I made them a crown. Then it became a thing. Having kids for multiple years doesn't help this. Calculus expects them. I'm getting pretty good at crafting them.
Depending on the timing, it may or may not include an embarrassing rendition of the Happy Birthday song.
There's a giant duct tape shark on my floor. Don't act surprised by this.