The school is a location first seen, but not named, in Petscop 2, and first mentioned by name by the Shadow Monster Man during Petscop 6, who spells out "WHERE IS THE SCHOOL" in letter blocks, when Paul asks the red TOOL the same question, it responds "You can't go back in time".
The school is mentioned by the pink TOOL in Petscop 7, who states that Marvin "ALSO WANTS 1000 PIECES FOR “MACHINE BEYOND SCHOOL BASEMENT STAIRWAY"". The note in Care's room in the Child Library briefly mentions "A young person walks into your school building".
The school is shown in a demo recording in Petscop 11, when the player explores it. It appears to be in a very out of place first person perspective. The school's interior is filled with lockers and several doors. The green TOOL, Marvin, and the Needles Piano are encountered in the school, as is a locker secured with a padlock which the Demo mode player is unable to open.