Bugs:Poptropica
This page details bugs of Poptropica.
Floating/Fly Glitch
In newer islands that use Action Script 3, if you are holding an item, press Spacebar multiple times until you see your character flying. This will allow you to go to areas in the game that are not normally accessable.
The HTML5 version still has this glitch.
Infinite Credits
Only in the Flash version of the game (which is now ported over to Steam), there is a glitch to gain infinite credits from the daily wheel: by closing/refreshing the page, the game will not detect that you have spun the wheel for the day (unless you landed on the grand prize), allowing you to gain a lot of credits easily without waiting for the next day.
The HTML5 version removed the daily wheel due to this glitch, and a daily credits system for that version is in its place.