The Royal National Lifeboat Institution has several online games designed to teach about water safety. Two of them — Build a Lifeboat and the Boating Game — are particularly good activities to help English Language Learners build their vocabulary.
In “Build a Lifeboat,” players choose various building materials they want to use to build different parts of a boat. Then the boat is placed in the water, and an analysis is shown about how seaworthy it would be. Students can learn the names of building materials and parts of a boat playing this game.
In the “Boating Game,” players have to go through “their” house finding things they would bring with them on a boat excursion. Here, students can learn the names for rooms of a house and a large number of other items.
I’ve placed both activities on my English For Beginners page at the bottom of the Vocabulary section.