umbrella blood rain
Finding a tampon (easier at a time when period party bags have been handed out), soak it thoroughly in red ink, and tie to the spoke of your victim's umbrella. When he opens it up, the tampon will swing and slap around, dripping its cargo on the child's clothes and head until he looks up and - hopefully - screams like a prize bitch.
If you have more time on your hands, put one on every spoke, like a grisly cork hat.
Any boy so fucking pompous as to own an umbrella deserves to briefly believe he has menses on his face.
written by excluded pupil, approved by Log