793 A.D. Vikings invade Lindisfarne, and from there the rest of England – so definitely have a Viking day. Again, the BBC is the best, and there is a list of crafts here. This family had a lovely Viking evening (with a lot of preparation!) Read some Norse myths or re-tell them with puppets.Write your name in runes, making a Viking helmet (and axes and shields), play Viking boardgames. And I love these Viking helmet cakes and these Viking longboat hotdogs! You can even make Viking soap out of conkers.
Bounty Day (celebrated a group of Pitcairn Islanders, descendents of the mutineers of HMS Bounty, landing on Norfolk Island in 1856)
World Oceans Day