Calvin's school has no known floors other than the ground level. Although the configuration of the entrance varies beween being raised and being on ground level in the strip, it always seems to provide access to the main hallway. The hallway projects left and right from the entrance; on its walls hang the students' lockers and at least one water fountain and clock. It is lit by neon arrays on the ceiling. The hallway is flanked by the classrooms, Principal Spittle's office and presumably various other offices, including the staff room (or teachers' lounge).
The recess court is accessed from a double door at the end of the hallway's left arm. The court contains swings, a set of two see-saws, a slide and monkey bars. The flagpole may be placed in the court; otherwise. The recess court expands into the back fields, used notably to run the school's baseball program.