At some point in each episode Tina's voice comes on the PA (except during The Dance Part 1, where Chaz's voice is heard instead) and tells two students, usually members of the clique Lee is investigating for that day, to report to Room 113b. Up until The Theme Team, the announcements and the room are generally ignored by Lee Ping and his friends. However, the episode reveals that the room is, in fact, a janitor's closet, with a picture of Alexander Nigma's brother Earl Nigma. The room, as revealed in The Dance Part 1, actually acts as an elevator that brings students to a secret, underground brainwashing laboratory.
- Episode 3 "Skate or Die" - Zed Point Conasty and Fred Connor
- Episode 4 "Math Math Revolution" - Irwin Dexter and Brad Myers
- Episode 5 "Friday Night Bites" - Brandy Silver and Kimmie McAdams
- Episode 6 "Dudes of Darkness" - Cyrus Xavier and Greta Von Hoffman
- Episode 7 "28 Sneezes Later" - Giuseppe Stern and Ed McFenney
- Episode 8 "Disco History Times" - Chaz Monorainian and Wayne Duncan
- Episode 9 "15th Graders" - Chopper McNeal and Freddy Patterson
- Episode 10 "Welcome to Factory Island" - Suzie Elliott and Camillio Martinez
- Episode 11 "The Tag Along" - Holger Holgaart and Skeeter Stevens
- Episode 12 "Down with Lee Club" - Robin Raven and Brad Von Chillstein
- Episode 13 "The Hair Incident" - McKenzie Phillips and Druscilla Duke
- Episode 14 "Chaz's Corner" - Steve Carb and Dean Clark
- Episode 15 "If the Shoe Fits" - Dick Andrews and Trevor Mars
- Episode 16 "The Camdidate" - Lou Black, Deuce Markowitz, and Jenny Jerkins
- Episode 17 "Outcast Times at A. Nigma High" - Emmett McKinley and Lee Webster
- Episode 18 "Double Date"- Evan Dansby And Trevor Mars
- Episode 19 "Mastermind" - Kimmie McAdams & Holger Holgaart
- Episode 23 "Tales From Decrypt" Camillio Martinez and Toni Williams
- Episode 26 "The Dance Part 1" - Brandy Silver and Camillio Martinez
- In later episodes of season two, the students called down to the room are the couples that the computer (in the lab) determines will be couples for the Save the Rainforest Dance.
- Although most characters are called down only once, some characters are called down multiple times:
- Brandy Silver has been called down twice.
- Kimmie McAdams has been called down twice.
- Holger Holgaart has been called down twice.
- Camillio Martinez has been called down three times.
- Camillio holds the record for being called down to Room 113b the most, having been called down three times: once in Welcome to Factory Island, once in Tales From Decrypt and once in The Dance Part 1.
- Oddly, Camillio is called down alongside a different female student each time: Suzie Elliot, Toni Williams and Brandy Silver in Welcome to Factory Island, Tales From Decrypt and The Dance Part 1, respectively.