It is revealed in "Absent Minded" that in April 2012, a toilet in the boys' restroom exploded, resulting in a flood, so the school had to be shut down for the rest of the day. In addition, it also caused Norm to take a leave of absence.
It is also revealed the school has been open at least since 1942, as one of the student records in the principal's office is labeled "Class of '42".
It would later be revealed in "She's All Bat" that the school has been open for even longer (specifically at least since 1874), as there is a document formed in that year called the School Club Act of 1874.
Lily is the only one of Lincoln's younger sisters not to attend this school, the reason being she is just a toddler.
"Tails of Woe" reveals that a genetically-altered rat named Cinnamon Bartholomew lives in the school.
The game Living Loud: Summer School reveals that the fifth grade classroom and the kindergarten are next door to each other, and that they are down a stairwell from the lockers.