let the stink bomb go
In the drawer cabinet in the detention room.
It it in the secret passage in the detention room on Big Nate Island.
in the detention room
The entrance to the secret room under the detention room is in the filing cabinet.
In the file cabinet, in detention, in the school.
It is in the secret store room behind the filing cabinet in the detention room on Big Nate Island. You need the blue prints from Nate's locker in order to access the secret room.
in the file cabnit to get there you must make the stink bomb
Go inside the file cabinet, go down to the secret room, and get the bell clapper. Before you go to detention, you have to open Nate's locker and get the blueprint showing the secret room.
You are only in detention to get into the filing cabinet, which has a secret passage behind it. Before chewing gum to get detention, there are two things you need : a stink bomb and the blueprint from Nate's locker. (see related question)
1. "use" the stink bomb in Detention room2. Open Nate's locker (combo is on comic strip you collect),click on a blue piece of paper (there are several blue papers)3. click on file cabnet
in the cabinet on big Nate island
up your butt