How do you get to the secret places on Club Penguin?

Head Quarters: Become a secret agent. Click on the gold M in the top right corner. You will get a quiz. If you get all of them right, you will become a secret agent.

Ninja Hideout: Play Card-Jitsu in the Dojo. Try to earn belts up to the black belt which is the highest belt. Then, challenge the Sensei. If you beat him, he will make you Ninja and you can go to a secret place.

EPF Room: First, you need to be a secret agent. Look at how to go in the Head Quarters to know how to be a secret agent. Then, enter the secret agent room. You click on your spy phone and click on Visit HQ or go in one of the change rooms in the Sport Shop. Make sure you have Penguin Elite Force on your Nintendo. If you do, go in the closet in the right.

G's Secret Lab: You need the Lab Coat and the Lab Wig to go in. It's members only. You buy it in the Gift Shop. The catalog changes every month so there might be a lab coat and a lab wig. If you have it, go in the Coffee Shop and go upstairs. Now go in the bookshelf.