Discovered on the White Board

A notice:

Bitter Lesson 17
from "How to be a baby!"

Don’t hang on the oven door, as it is liable to fall open and hurt you badly.

(For the record: the oven was not turned on at the time of the incident which led to the above words of wisdom; and the only thing "badly" hurt was a toddler’s dignity.)

(As for Bitter Lessons 1-16, I do not know what they are, but I’m told a certain big sister is compiling a book.)