Besides from eating, another popular activity for your day in Peng Chau Island is to go sightseeing (obviously). Peng Chau Island is quite an ideal place to go for a little bit of sightseeing as the island is relatively small, and the hot-spots are quite close. Another good thing about Peng Chau Island is, you can't really get lost. Therefore, many schools and clubs choose this island for a little bit of scout work or a simple game of scavenger hunt.
Ah, finger hill. The highest point in Peng Chau Island gives you a panoramic view of the island itself, Disneyland, Lamma Island, Lantau Island (Discovery Bay), and Hong Kong Island.