On the 7th of September Club Penguin has updated in 2007 and 2010. In 2007 there was one update, a new penguin style for the month. In 2010 there was a new field op and new stamps.
The September 2007 Penguin Style featuring back to school themed items. Items such as the Letterman Jackets, Backpacks, and T-Shirts made an appearance.
In 2010 the 13th field op mission was released. For this mission you had to go to the Hidden Lake. The mission was completed by bypassing the system, which was done by matching data with the firewall to break through. Five new stamps were also released for penguins to unlock. The stamps were EPF related. They are the ones you unlock for having 1, 5, 10, 25, and 50 EPF medals. While field ops no longer exist, you can still earn medals through the Spy Drills game at the EPF Command Room.
Want to see and learn more? Check out these pages about the topics mentioned above.