You may visit the Dunwich Museum which gives the history of the town, including a model of Dunwich in the 12th Century and the history over 1500 years. Also includes interactive displays, tales of smuggling and information on local wildlife. Admission is free (donations always welcome).
Walk along the beach and look for fossils (or maybe bones)
Eat Fresh Fish and Chips within sight of the sea at one of the finest fish restaurants in East Anglia.