Island Medallion

The Island Medallion, or simply Medallion is a medal as a reward for you if you complete an island. The Medallion comes with 50 free credits and could be worn by the Poptropican.

Islands
The easiest way to earn the Medallion on each Islands is to complete the quest. Each islands have different ways to complete quest. Here's a description on each island's main quest :

Credits
Completing Islands in Poptropica is the easiest and simplest way to receive credits. When the player completed an Island, they will receive 100 credits to spend in the Poptropica Store. However, since late 2011, completing an Island will receive 50 credits only.

Restart
Starting July 6, 2011, Poptropica started allowing players to replay islands, while keeping all the Island Medallions they had already earned. The medallion they received from completing once will not be disappear. . However, they will not receive credits as well.